QGroundControl - Radio Setup Issue - RadioMaster TX12 MarkII CC2500 - R81-V2 Receiver

I’m having Issue with a radio setup in my drone. I have been able to bind R81 with RadioMaster TX12 but during setup QGroundControl status is “Radio Not Ready - Please turn on Transmitter.” I have connected R81 to Pixhawk 6x RC IN pin. I have attached screenshot of an Issue.

PX4 Pro Version 1.14.3