One Kalender meldet 1 Fehler

Ich benutze seit einem Jahr das One Kalender.
Seit längerem (aber ich weiß nicht, wie lange) kommt nach jedem neu eingetragenen Termin diese Meldung (One Kalendermeldet einen Fehler).
Geht man auf Anschauen kommt ein ellenlanger Text

Failed to connect to www.googleapis.com/172.217.16.74:443

Action: CheckAccountStatus

XCalendarApp.ProviderBase.Exceptions.AccountRequestException: Failed to connect to www.googleapis.com/172.217.16.74:443 ---> XCalendarApp.Common.Net.HttpException: Failed to connect to www.googleapis.com/172.217.16.74:443 ---> System.Net.WebException: Failed to connect to www.googleapis.com/172.217.16.74:443 ---> Java.Net.ConnectException: Failed to connect to www.googleapis.com/172.217.16.74:443
at Java.Interop.JniEnvironment+InstanceMethods.CallVoidMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x0006e] in <138b7f096ddd4c04aaddf98bfacad711>:0
at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeAbstractVoidMethod (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) <0x708186eba8 + 0x0007b> in <138b7f096ddd4c04aaddf98bfacad711>:0
at Javax.Net.Ssl.HttpsURLConnectionInvoker.Connect () <0x707dd1161c + 0x00053> in :0
at Xamarin.Android.Net.AndroidClientHandler+<>c__DisplayClass44_0.b__0 () [0x0005a] in :0
at System.Threading.Tasks.Task.InnerInvoke () <0x707f0fc578 + 0x00083> in <0184526b6b704bca813f769f0c4dafbc>:0
at System.Threading.Tasks.Task.Execute () <0x707f0fc244 + 0x00037> in <0184526b6b704bca813f769f0c4dafbc>:0
--- End of stack trace from previous location where exception was thrown ---

at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x0012e] in :0
--- End of inner exception stack trace ---
at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x0017e] in :0
at Xamarin.Android.Net.AndroidClientHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x707dd060bc + 0x0066b> in :0
at System.Net.Http.HttpClient.FinishSendAsyncBuffered (System.Threading.Tasks.Task1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) [0x0017e] in <8db4ced7ddc546c7bcace5908fa2ab15>:0
at XCalendarApp.Common.Net.CalendarHttpClient.ExecuteRequest (System.Threading.CancellationToken cancellationToken, System.String url, System.String httpMethod, System.String requestContent, System.String soapAction) [0x00264] in <58bc20e4d8694b898d3805925afd9339>:0
--- End of inner exception stack trace ---
at XCalendarApp.Common.Net.CalendarHttpClient.ExecuteRequest (System.Threading.CancellationToken cancellationToken, System.String url, System.String httpMethod, System.String requestContent, System.String soapAction) [0x00428] in <58bc20e4d8694b898d3805925afd9339>:0
at XCalendarApp.Common.Net.JsonHttpWebRequest.Execute (System.Threading.CancellationToken cancellationToken, XCalendarApp.Common.Net.XHttpClientRequirements httpClientRequirements, System.String url, System.String authorizationHeaderToken, XCalendarApp.Common.Net.HttpMethod httpMethod, System.String contentType, System.String requestData, System.Collections.Generic.Dictionary2[TKey,TValue] requestHeaders) <0x707b1d90e4 + 0x001d3> in <58bc20e4d8694b898d3805925afd9339>:0
at XCalendarApp.ProviderBase.Json.OAuthJsonBase.ExecuteRequest[T] (System.String baseApiUrl, System.String param, XCalendarApp.Common.Net.HttpMethod httpMethod, System.String requestData, System.Boolean refreshAllowed, System.Collections.Generic.Dictionary2[TKey,TValue] requestHeaders) <0x707af92690 + 0x0054f> in <0b31b98b0b1c481f8151568cac7e27ba>:0
--- End of inner exception stack trace ---
at XCalendarApp.ProviderBase.Json.OAuthJsonBase.HandleExecuteRequestException (XCalendarApp.Common.Net.HttpMethod httpMethod, System.String requestData, System.Boolean refreshAllowed, System.String url, System.String responseStr, System.Exception ex) <0x707af7c824 + 0x00190> in <0b31b98b0b1c481f8151568cac7e27ba>:0
at XCalendarApp.ProviderBase.Json.OAuthJsonBase.ExecuteRequest[T] (System.String baseApiUrl, System.String param, XCalendarApp.Common.Net.HttpMethod httpMethod, System.String requestData, System.Boolean refreshAllowed, System.Collections.Generic.Dictionary2[TKey,TValue] requestHeaders) <0x707af92690 + 0x007ab> in <0b31b98b0b1c481f8151568cac7e27ba>:0
at XCalendarApp.GoogleProvider.GoogleApi.GetCurrentUser () <0x707af17f90 + 0x00107> in :0
at XCalendarApp.GoogleProvider.GoogleAccount.CheckProviderAccountInfo (XCalendarApp.Model.Settings.AccountSecurityInfo accountSecurityInfo) <0x707af13e74 + 0x001e3> in :0
at XCalendarApp.ProviderBase.AccountProviderBase`8[TCachedCalendar,TProviderCalendarItem,TCachedAppointment,TProviderAppointmentItem,TCachedContacts,TCachedContact,TProviderContactItem,TAppointmentDbData].CheckAccountStatus (XCalendarApp.Model.Data.SyncResults.AccountSyncResult accountSyncResult) <0x707af8b4c0 + 0x001b7> in <0b31b98b0b1c481f8151568cac7e27ba>:0
RequestType: Get
RequestUrl: https://www.googleapis.com/oauth2/v1/userinfo?access_token=*********************************************************************************************************************

Inner exception: XCalendarApp.Common.Net.HttpException: Failed to connect to www.googleapis.com/172.217.16.74:443 ---> System.Net.WebException: Failed to connect to www.googleapis.com/172.217.16.74:443 ---> Java.Net.ConnectException: Failed to connect to www.googleapis.com/172.217.16.74:443
at Java.Interop.JniEnvironment+InstanceMethods.CallVoidMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x0006e] in <138b7f096ddd4c04aaddf98bfacad711>:0
at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeAbstractVoidMethod (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) <0x708186eba8 + 0x0007b> in <138b7f096ddd4c04aaddf98bfacad711>:0
at Javax.Net.Ssl.HttpsURLConnectionInvoker.Connect () <0x707dd1161c + 0x00053> in :0
at Xamarin.Android.Net.AndroidClientHandler+<>c__DisplayClass44_0.b__0 () [0x0005a] in :0
at System.Threading.Tasks.Task.InnerInvoke () <0x707f0fc578 + 0x00083> in <0184526b6b704bca813f769f0c4dafbc>:0
at System.Threading.Tasks.Task.Execute () <0x707f0fc244 + 0x00037> in <0184526b6b704bca813f769f0c4dafbc>:0
--- End of stack trace from previous location where exception was thrown ---

at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x0012e] in :0
--- End of inner exception stack trace ---
at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x0017e] in :0
at Xamarin.Android.Net.AndroidClientHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x707dd060bc + 0x0066b> in :0
at System.Net.Http.HttpClient.FinishSendAsyncBuffered (System.Threading.Tasks.Task1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) [0x0017e] in <8db4ced7ddc546c7bcace5908fa2ab15>:0
at XCalendarApp.Common.Net.CalendarHttpClient.ExecuteRequest (System.Threading.CancellationToken cancellationToken, System.String url, System.String httpMethod, System.String requestContent, System.String soapAction) [0x00264] in <58bc20e4d8694b898d3805925afd9339>:0
--- End of inner exception stack trace ---
at XCalendarApp.Common.Net.CalendarHttpClient.ExecuteRequest (System.Threading.CancellationToken cancellationToken, System.String url, System.String httpMethod, System.String requestContent, System.String soapAction) [0x00428] in <58bc20e4d8694b898d3805925afd9339>:0
at XCalendarApp.Common.Net.JsonHttpWebRequest.Execute (System.Threading.CancellationToken cancellationToken, XCalendarApp.Common.Net.XHttpClientRequirements httpClientRequirements, System.String url, System.String authorizationHeaderToken, XCalendarApp.Common.Net.HttpMethod httpMethod, System.String contentType, System.String requestData, System.Collections.Generic.Dictionary2[TKey,TValue] requestHeaders) <0x707b1d90e4 + 0x001d3> in <58bc20e4d8694b898d3805925afd9339>:0
at XCalendarApp.ProviderBase.Json.OAuthJsonBase.ExecuteRequest[T] (System.String baseApiUrl, System.String param, XCalendarApp.Common.Net.HttpMethod httpMethod, System.String requestData, System.Boolean refreshAllowed, System.Collections.Generic.Dictionary`2[TKey,TValue] requestHeaders) <0x707af92690 + 0x0054f> in <0b31b98b0b1c481f8151568cac7e27ba>:0
Inner exception: System.Net.WebException: Failed to connect to www.googleapis.com/172.217.16.74:443 ---> Java.Net.ConnectException: Failed to connect to www.googleapis.com/172.217.16.74:443
at Java.Interop.JniEnvironment+InstanceMethods.CallVoidMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x0006e] in <138b7f096ddd4c04aaddf98bfacad711>:0
at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeAbstractVoidMethod (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) <0x708186eba8 + 0x0007b> in <138b7f096ddd4c04aaddf98bfacad711>:0
at Javax.Net.Ssl.HttpsURLConnectionInvoker.Connect () <0x707dd1161c + 0x00053> in :0
at Xamarin.Android.Net.AndroidClientHandler+<>c__DisplayClass44_0.b__0 () [0x0005a] in :0
at System.Threading.Tasks.Task.InnerInvoke () <0x707f0fc578 + 0x00083> in <0184526b6b704bca813f769f0c4dafbc>:0
at System.Threading.Tasks.Task.Execute () <0x707f0fc244 + 0x00037> in <0184526b6b704bca813f769f0c4dafbc>:0
--- End of stack trace from previous location where exception was thrown ---

at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x0012e] in :0
--- End of inner exception stack trace ---
at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x0017e] in :0
at Xamarin.Android.Net.AndroidClientHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x707dd060bc + 0x0066b> in :0
at System.Net.Http.HttpClient.FinishSendAsyncBuffered (System.Threading.Tasks.Task`1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) [0x0017e] in <8db4ced7ddc546c7bcace5908fa2ab15>:0
at XCalendarApp.Common.Net.CalendarHttpClient.ExecuteRequest (System.Threading.CancellationToken cancellationToken, System.String url, System.String httpMethod, System.String requestContent, System.String soapAction) [0x00264] in <58bc20e4d8694b898d3805925afd9339>:0
Inner exception: Java.Net.ConnectException: Failed to connect to www.googleapis.com/172.217.16.74:443
at Java.Interop.JniEnvironment+InstanceMethods.CallVoidMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x0006e] in <138b7f096ddd4c04aaddf98bfacad711>:0
at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeAbstractVoidMethod (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) <0x708186eba8 + 0x0007b> in <138b7f096ddd4c04aaddf98bfacad711>:0
at Javax.Net.Ssl.HttpsURLConnectionInvoker.Connect () <0x707dd1161c + 0x00053> in :0
at Xamarin.Android.Net.AndroidClientHandler+<>c__DisplayClass44_0.b__0 () [0x0005a] in :0
at System.Threading.Tasks.Task.InnerInvoke () <0x707f0fc578 + 0x00083> in <0184526b6b704bca813f769f0c4dafbc>:0
at System.Threading.Tasks.Task.Execute () <0x707f0fc244 + 0x00037> in <0184526b6b704bca813f769f0c4dafbc>:0
--- End of stack trace from previous location where exception was thrown ---

at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x0012e] in :0
--- End of managed Java.Net.ConnectException stack trace ---
java.net.ConnectException: Failed to connect to www.googleapis.com/172.217.16.74:443
at com.android.okhttp.internal.io.RealConnection.connectSocket(RealConnection.java:147)
at com.android.okhttp.internal.io.RealConnection.connect(RealConnection.java:116)
at com.android.okhttp.internal.http.StreamAllocation.findConnection(StreamAllocation.java:186)
at com.android.okhttp.internal.http.StreamAllocation.findHealthyConnection(StreamAllocation.java:128)
at com.android.okhttp.internal.http.StreamAllocation.newStream(StreamAllocation.java:97)
at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:289)
at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:232)
at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:465)
at com.android.okhttp.internal.huc.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:131)
at com.android.okhttp.internal.huc.DelegatingHttpsURLConnection.connect(DelegatingHttpsURLConnection.java:90)
at com.android.okhttp.internal.huc.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:30)

Muss ich mir Sorgen machen?