I received my Anti-Fatigue Mat but the largest one was discolored from top to bottom on the end I need to return it for a replacement what is your procedure for turning it for a replacement it came as a set and the small one is fine. I had texted you on the other text sent to me but for some reason it did not reach you so I deleted it.  Please respond. The smallest one looks and feels great, the largest one felt good it just has the odd spot near the end. Not sure how to rate it.