Hi akn,
There is no way to disable a specific band. You should create a new set band with AT!BAND and then select this set for device.
Ex: new set with B1,2,3 -> AT!BAND=10,“TEST”,0,7,0
Remember unlock device before set band (AT!UNLOCK=“A710”)
You need to use at!entercnd=“A710” to allow you to set the band mask with at!band. The command at!unlock is to level 3 unlock a unit which is not available on normal production units.