Fatal inventory bug!!!!

Well, I started to play in my world like I normally do, when I realize that all my inventory was empty!! I don't die before, and I don't save my inventory in a chest, it just disappeared, this is a fatal bug because I just got most items of the new ore "netherite" and I'm feel so bad. I had to start of 0 now but please fix this bug.

P.D.

I have attached some before and after photos from my inventory, the ones before are a bit outdated because I was taken by surprise by this terrible bug.