I am working with the Zeta Phantom FX-61 with Pixhawk and want to make it fly in mission mode. I create mission plan with 1 waypoint being loiter type and specified the radius and the altitude. I manually takeoff and everything is good about manual flight but when I switch to mission mode in the air via RC mode switch, it aggressively descends and I reswitch to manual mode. What may be the reason for this behaviour? I repeatedly try with calibration steps but no success. Also, the sdlog2 stops to log just after I manually takeoff, so the logs are all about preflight.