No way that is leather, did you buy a used seat?
OUCH! that is some big bill for what you got. I hope that isn't what RDL calls leather, maybe the tech used the wrong material? Whatever material it is, it should certainly hold up much longer than yours has. Good luck in getting the problem resolved, THEIR reputation is at stake here. 🤔
I have an office chair doing the same thing over most of the surface. It felt like leather when new but I now realize it is pleather which is synthetic it has been indoors and never had any chemicals used on it.