I know this topic is a few days old, so if it's already fixed for you, ignore this please.
I checked about 10 of mine that led to different places and they're all working for me. You might need to clear your notifications out and let it start fresh. Forumotion might just be glitching and getting thread numbers wrong. It can happen when a thread is moved, splits, or gets deleted.
Just click on See all the notifications, scroll to the bottom, and click delete all. Wait for a few more notifications to pop up in the next day or so and see if you're still experiencing the issue.
I'll give you another one to see if it works. @Klown