I got that message today after a flight. The gimbal isn't moving nor stabilizing.
Any ideas?

Have you tried manualy moving the gimbal when turned off, and the gimbal calibration through the fly app?

Hello there Moshe.mmm. I am sorry for the trouble this has caused and thank you for reaching out. May we know before this issue happened was there a hard landing or a crash that happened to the said DJI Drone? In addition kindly please try to calibrate the gimbal of the said DJI drone to see if the issue will still persist. Thank you.