Are there fibers stuck in the slices that are not allowing it to heal? Someone suggested to use a giant rubber eraser to remove any fibers stuck in the slices. I usually find after the fibers are out the Olfa mats do seal themselves fairly well. Others do say to lay the mat in the bottom of the tub with tepid water if the matt is too dry. I believe the soaking method is for the plain flat mat and not the revolving kind.