GTen has an update for the UpAir One V4 that has a PX4 board fitted.
this should help you fix problems with “No MAV Data” showing on your screen.
The update is easy, but be 100% sure your UpAir is a V4 with a PX4 board, it will not work on a V3 or older
They have written a simple manual how to do it, You can download the manual here
The firmware is available for Download here This is a ZIP file