The deposit can be refunded, but whether the university can keep the certificate for four years is a problem. If you have any questions about school fees, you can ask the media to come to the school for investigation and interview. The evidence is the easiest, and the receipt will be OK when your friend goes to school. Be bold and get twice the result with half the effort. Otherwise, they will not attach importance to your complaint to the education department. I have a friend whose school is like this.