I stopped receiving notifications of alerts by email, according to journalctl the connection with SMTP is being cut/closed without sending it.
May 25 09:45:41 promised alertmanager[94081]: ts=2023-05-25T12:45:41.743Z caller=notify.go:732 level=warn component=dispatcher receiver=Operations integration=email[0] msg=" Notify attempt failed, will retry later" attempts=3 err=“create SMTP client: read tcp 10.100.40.185:44628->200.198.4.27:587: read: connection reset by peer”
Thanks,
Cássio