Notification issue with IOS 15

Ever since I updated to IOS 15, my notification "buttons" (if that's the right description) don't work correctly.

My Instagram icon shows I have unread notifications (when I don't), my mail icon shows I have unread email (when I don't), my message button doesn't show any unread messages (when I actually have some) etc etc.

I've played with my notification settings, I've done a soft reset etc and nothing seems to fix it.

Any suggestions please?

Thanks!