Problem with Snapchat?!? Wtf happened??

A year ago, my ex sent an invitation on Snapchat that I ignored. I use Snapchat on very rare occasions.

And this evening I realised he is in my list of friends and I apparently saw a pic he sent me two months ago...wtf, I never ever did that, is it possible snapchat went crazy idk😅

I thought someone around me using my account but no one would do that...

Anyone encountered the same weird problem??