Spitz AX (GL-X3000) Two potential issues with "Traffic Statistics"?

(1) Traffic values do not match on my Spitz AX:
Traffic Statistics: Upload 3.49 GB, Download 15.32 GB.
Clients: Total about 76 GB for three clients.

(2) “Disable Auto Saving Of Traffic Statistics” setting is not saved. For me it turns on again automatically after reboots.

Infos:
Firmware Type: release20300 / 2023-04-25 18:03:11(UTC+08:00).
Network Acceleration is disabled.

You can see the actual traffic with the following AT command (note :'?'is also part of the AT instruction)

5G: AT+QGDNRCNT?
4G: AT+QGDCNT?