No more mail notifications

Hello MT team, since 1.3. I no longer get an email notification that someone has written something about a subscribed topic or a PN. I’ve already switched off the notification in the cockpit –> saved –> turned it on again –> and saved it again, but it didn’t help. I can’t find any mails from you in my spam folder at GMX either. What can it be, how can I restore it? Thank you for an answer! Greeting Rainer