If you notice that one of your classes has been deleted, there are a couple possibilities.
Class deleted by owner or administrator
Class owners or administrators can delete classes they manage. It's possible your class was deleted by one of them.
Class deleted for inappropriate content
Classes on Quizlet are for studying.
If your class was deleted, it may have been because it wasn't education or study related, or it may have contained inappropriate content or activity. Our Terms of Service lists the types of content and activity we don't allow.
Please keep your use of Quizlet study-oriented. Thanks!