The same problem a few days ago, never happened to me before, plane with Pixhawk 4 Mini and Holybro Telemetry.
Simply the telemetry antenna interfered with the signal. Lower the telemetry power and change the location or position of the antenna, first of all test the entire connected plane on the balcony except telemetry, and connect MP by cable to be sure that it is that; It worked for me, greetings.