Issue: @Mention being funny

This has happened twice

I get notified for an @mention but it doesn't appear on the mentions tab.
It's not very clear in the picture, but it states today's date being the 10th and the last update for a mention was the 8th. I had a mention on the 9th as well, which also didn't appear. that was ignored cause I thought it might have been a little glitch..
It started round about the same time started being active on invisible mode. Do you think it could be related?