Preflight errors : GPS and AHRS error lead to impossible pre arm check

Hello, I just finished installing and doing all the set up of my qav 250 Holybro. I am using QGroundControl with a Pixhawk 4 Mini and all the settings are now correctly done but when I want to arm the drone I receive error messages linked to GPS datas or bad AHRS. I get messages of preflight fails such as “compasses 47° inconsistent” or “GPS Horizontal Pos Error too high” or “high accelerometer bias” …
I am quite new with QGroundControl and drones and a little help would be really nice :slight_smile: