I'm using Azure Notification Hub to send Push Notifications (from an Azure web app), and am occasionally getting errors like this in my logs:
Microsoft.Azure.NotificationHubs.Messaging.MessagingException: Unexpected exception encountered TrackingId:c9d0dc7e-c98a-4f38-bfb4-cff867b0aa02,TimeStamp:2020-09-02T14:05:12.0050613Z
---> System.Threading.Tasks.TaskCanceledException: The operation was canceled.
---> System.IO.IOException: Unable to read data from the transport connection: The I/O operation has been aborted because of either a thread exit or an application request.
---> System.Net.Sockets.SocketException: The I/O operation has been aborted because of either a thread exit or an application request
I'm only sending a max of 10 messages every minute using the NotificationHubClient package from Nuget (v3.3.0). These errors only started happening within the past week, but I'm getting a couple dozen a day now. I cannot reliably reproduce the error, it only seems to happen now and then, with a different set of recipients each time. I'm using the free Notification Hub tier, so I don't have access to per-message telemetry.