Triggering precision landing

[2vin2vin]

Hi, I am new to pymavlink and I have been trying precision landing. master.mav.command_long_send( master.target_system, master.target_component, mavutil.mavlink.MAV_CMD_DO_SET_MODE,0, mavutil.mavlink.MAV_MODE_FLAG_CUSTOM_MODE_ENABLED, 8,0,0,0,0,0) where master is connected to the drone 8- I took from https://github.com/PX4/PX4-Autopilot/blob/main/src/modules/commander/px4_custom_mode.h as it links to precision landing command. But it doesn't seem to trigger the precision landing mode in the QGC. I am working on px4.