Hi, I am very new to DJI Mavic air 2 and when I go at high altitdues, the Gimbal is rotating automatically and its very annoying...did any one expereince the same issue?

Sample video is at https://www.youtube.com/watch?v=JEcFCUnG0jk

Are you referring to the last few seconds of that clip?  Could it be that you've made your IMU "dizzy" with all that rotation on the way up and perhaps the GPS is taking a few seconds to lock back on?  How many satellites are you seeing when this happens?

It hurts my eyes and brain watching the video.

yeah, agree with Northwood, and it could be caused by inertia or buffer of the drone movement.

maybe calibrate the IMU and gimbal.

Hi. I am sorry for the trouble this has caused. With regards to this concern. As Jonatan.C.N advised at post #3, kindly please calibrate the IMU to isolate the issue. Please keep us posted for further assistance. Thank you.

Your video looks like the aircraft itself is yawing as the gimbal faces down.  

As you ascended were you giving a bit of left stick (assumed mode 2) yaw?  Using the "pinch" method on the sticks can help (for many users). or make wanted yaws and ascends easier to control..

That is how I  interpreted your question and video.