Also, I would like to know if there is any chance to know who did it
Hi Rebeca Alvarado Ramírez - The "undo trick" that Jennifer Carpenter is referring to is spelled out in a bit more detail here: Undeleting things in Canvas
However, a few things struck me in your question. You said the words "group assignment." Assuming that this was a true group assignment, creating along the lines of what is mentioned in this lesson, a group member can NOT delete a submission. Heck, even faculty cannot delete a submission. Did you check SpeedGrader for earlier submissions, just in case?
On the other hand, they CAN delete material in their own group files area; that may mean getting Canvas Support involved since I'm not too sure even a Canvas admin can trace that in their user log.
Have you tried Canvas's undo trick? I don't think you can find out who though.
Thanks, Jennifer. I will look for the trick... usually, the uploaded documents remain in the assignment, but my students deleted on purpose because they copied from other students, that's why I want to know who did it
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