Exception indicating that something went wrong with the underlying HTTP request to App Services. The exact cause is in the exception message.
Errors resulting in this exception are outside the apps control and can be considered temporary. Retrying the action some time in the future should generally be safe, but since this potentially requires corrective measures in either the apps network environment or on the server, you should log this error for further analysis.
Note, HTTP responses that indicate problems that can be fixed in the app will throw a more specific exception instead, e.g.
401 - AuthenticationRequired will throw InvalidCredentialsException.