Check the barcode of the book: First, please make sure that the barcode of the book is clearly visible and has not been damaged or polluted. If the bar code is defaced, you can try to scan the bar code with the "scan code repair" function on the self-service book returning machine and wait for the system to repair it automatically.
Rescan the book: If there is nothing wrong with the barcode of the book, you can try to rescan the book. Put the book in the scanning area of the self-service book returning machine, wait for the system to read the barcode and return the book automatically.
Confirm the return information: please pay attention to confirm whether the return information is correct during the return process. If the return information is wrong, you can re-enter or modify the relevant information and try to return the book again.
Contact the staff: If the above methods can't solve the problem, you can contact the staff or administrator of the library. They can help you solve problems and provide further help and guidance.
When using the self-service book returning machine in Chongqing Library, don't worry too much if you encounter the problem of book returning failure. You can try the above methods to solve the problem and contact the staff for more help.