Ardupilot drone with 2 Herelink RCs


I’m trying to configure a drone with Multiple Radio Controllers. following the link (link) .

Even though the telemetry is received normally by the 2 RCs, the control of the drone is not what we expected. It seems that the drone is receiving commands from both RCs, and the 2nd RC cannot perform all actions (for example disarm).
Additionally, if the first RC is shutdown, and afterwards reconnected, it is able to regain control (when it should leave the control to the RC2).

Any idea of what I could be doing wrong?

Does anyone have any inputs?