Error arming and "offbaord mode not currently availble"

Hello I hope everyone is well. I have two pix hawk 4 drones that work flawlessly one night and then you come in the next morning and it will not work.

One drone has the issue of MAV_CMD_COMPONENT_ARM_DISARM temporarily disabled after updating the firmware. (on a side note does anyone know where I can find a clean 1.9.2 firmware download?)

the other drone gets a “offbaord mode not currently available” in q ground control. It will arm in q ground control but not through mav link.

another question I have is does anyone know the setting to turn of tx and rx connection to be able to arm? Thanks. I know this is a lot. please help if you can