Yes it is the ribon cable , unfortunately DJI didn’t want to honor the warranty (for gimbal is up to 6 month by the way) and they wanted to charge me 220$ for repairs so I fixed it myself for 11$ ,the cost of ribon cable on eBay.
I was reading also that for other mavic pro owners this issue was repaired by DJI at no cost,so is this being subjective?!