Do not rule out the possibility of administrator's operation error ~ even if the system does not make mistakes, the administrator's operation may make mistakes. Since the system shows that it has been returned, you still have this book in your hand. Basically, you can identify the operation problems of the administrator. Please ask the administrator to find out the specific reason.

Supplement: Since last year, Shenzhen has implemented one-card lending and returning, so books borrowed from Baoan can be returned to Futian Library. If you confirm that the periodicals you borrowed have not been returned, the system will show that they have been returned. Please contact the librarian for help. I hope I can help you.