If you have the following situations with the books you have borrowed, you cannot renew them online:

1. The renewal period has not been reached: Renewal can be done seven days before the due date.
2. The book has been reserved by another reader.
3. The book is overdue for more than three days. Additionally, if you have accumulated overdue fines exceeding 150 NT dollars, you cannot renew books. If you have excluded the above situations and still cannot renew the books, please contact us at cirlib@mail.nsysu.edu.tw or call 07-5252000#2426 for further assistance.