Why is the HMI pop-up file incompatible for RDC6685U controller?

The control system I am using with my device is RDC6685U, and I encountered an issue while operating the HMI interface. When attempting to open or upload a file, the system pops up a prompt saying 'File incompatible'. Although the file format is consistent with the system requirements, the problem still exists, resulting in the inability to smoothly transfer data and update settings. Who can help me solve this problem? Thank you in advance for any suggestions!