Wireless Joint

I am trying to change my cellular mode from Automatic to 4G Only. I have tried the "DISCONNECT CURRENT MODEM" button then I selected 4G Only at the Change Cellular Mode field, then selected "APPLY MODE CHANGE".

It seems to work at first but keeps resorting back to Automatic mode for some reason. What am I doing wrong?

System
Hostname ROOter
Model ZBT-WE826 (16M)
Architecture MediaTek MT7620A ver:2 eco:6
Firmware Version GoldenOrb_2019-03-10 ( OpenWrt 18.06.1 )
Kernel Version 4.14.63
Local Time Mon Dec 16 10:09:25 2019
Uptime 0h 45m 45s

What modem?

Quectel EC25

After going back and re-reading my post in the Tower forum, I noticed you suggested an AT command:
AT+QCFG="nwscanmode",3,1

Should I ignore the cellular mode field in my picture above and simply enter this command in the AT Command Terminal?

That would be up to you. I do not know if that version of GoldenOrb will change the mode with the button.

The AT Command should change it at the modem level.