what are you supposed to do if your teacher looses your paper and you know you turned it in but it says in the grade book missing

talk to your teacher

Explanation:

talk to your teacher about your missing assignment. they will look for it for you, but if they can't find it, you might have to redo the assignment. they might also give you an exemption on the assignment, but that's unlikely.

if you're worried about talking to them face-to-face, you could email them.