I have a office chair but everytime I try to use water on it it just leave a big stain what should I do ?
Try cleaning the chair again I would use carpet cleaner. Put a fan on the chair to see if it dries. I think maybe the water stain has not dried completely. If that does not work have it clean professionally they may have something they can get the stain out of the fabric.
Clean the whole seat area then it will be the same color/shade. You are probably seeing the difference in color. The part you have cleaned being lighter than the unaffected area that you did not clean. Hope this makes sense...