My mavic pro premium starts up with the magnetic interference, check app error. and I can not conect to app ( DJI Go 4 or Litchi) through my cell phone or tablet. I thought I saw on youtube that you can toggel the S/P switch and the prompt for compass calibration would come up on the RC screen, that didn' t happen , I was ableto calibrate the IMU with DJI Assist using the USB connection. Can anyone help?