Caused by rubber backed mats is a common problem. It usually is a permanent condition.
I would go to the store that sold you the mats and request replacement of your flooring because of the defective product they sold you. I normally am not in favor of litigation, but in this case, there are just too many mats on the market that cause this, and they (stores and manufacturers) need to start standing behind their defective product.
Good Luck!