Problem with chain tensioner, advice needed!

Hello fellow folders, I have a situation with one of my c lines, as you can see in the video, the chain tensioner flexes when the bike is folded and when the pedals are turned backwards (as for making space for the complete fold). I have pretty much tried a lot of things: from taking the chain tensioner off, cleaning it, cleaning the chain, the cassette, aligning it all back, but still the samw problem persists. I also watched some of the videos for chain tensioners/deraillers from the Billiant Bikes lady but nothing there would solve the problem. I examined the chain tensioner, its seems pretty functional, the bike is not even three years old. When riding, all seems all right and there are no issues. What do you suggest I should do apart to before changing the chain and/or chain tensioner? Anyone else had the same situation?