Znuny and ((OTRS)) Community Edition

I have Znuny 6.4 and after the upgrade to this version the connection with Oauth2 to Exchange has been lost and recreated, but now I have this error: Could not send message to server: ****** SendAsDenied; ***** not allowed to send as ******; STOREDRV.Submission.Exception:SendAsDeniedException.MapiEx...