Game breaking glitch if you try to choose the assassin class. Happened on console, after some searching, it's a documented problem on computers as well as the switch port.
Ubisoft developers tell people to just pick a different class. That was a thread from years ago. It's still a thing.
My last save was 6 hours ago. That sucks. That really really sucks. The "just don't do it" response only adds insult to injury.