Returning a whiteboard paint coated surface to its full dry-erase capability can be accomplished in several steps, which include (1) carefully cleaning your erasers and afterwards utilizing them to clean your surface; (2) making use of a clean microfiber cloth to do the task; and (3) using a tidy microfiber cloth along with water alone or with a water-based whiteboard cleaner.
For a more detailed explanation on the above-mentioned means, read the full article at:
https://www.remarkablecoating.com/how-do-you-restore-a-whiteboard/