THIS HAS HAPPENED TO ME AS WELL!
Even worse some notifications popped up randomly then when I check there are no new messages then weeks later it shows up????
I just discovered that I have loads of unread message 'requests' in my X DMs, some of them 30+ weeks old. Was never served a notification for them, so had no idea they were there. I'm very sorry if I've ignored you as a result 🙈
