Huge issue which just made me lose 20 minutes of footage.

I set the active track to follow from behind, 20.minutes into my ride it glitches, drone starts to land and the screen freezes. Battery level looked right, joysticks weren't touched.

I had to force stop the app on my Note 20 Ultra. The drone was recording, but when looking at files it wasn't there.

This is the first time it's happended to me. Any fixes/recommendations?

When you say the file wasn't there, is that from the Fly app or the microSD card on the MA2? Also, for 4K recordings they are broken up into separate files of 4 min and 50 secs long, so there should be at least 3 files (the 4th one maybe corrupted) if it was actually recording. Sounds like from the description the Fly app crashed (not unusual with v1.4.8) which then caused the Active Track to stop followed by the forced landing.

Can you post the log file link, or the actual log file (zipped) itself?

Hi there. Thank you for reaching out and we're sorry for the trouble. As Pappy3 mentioned in post #3, could you please try to check the SD card if the said file was there? Also, did you receive a specific error message when you experience the said issue? You may try to uninstall and reinstall the app on your mobile device and have a test flight and check if there would be some changes. Please keep us posted. Thank you!

If you are using DJI Fly App v1.4.8 that could be the reason as many users have reported issues with that version.  I uninstalled v1.4.8 and installed v1.4.4 and the Fly App crashes went away completely.  

You can get previous versions here.  DJI FLY APP Previous versions