Stain wont peel if done right, most likely it was stained in the sun or
on a hot surface, or just to hot out. Read a can label and call any
manufacturer, surface temp is critical. If it is peeling washing is one
step scraping is another. For the paint they are using call the store
or company and get out the representative, we cant see it, but this is
common to have done. What brand stain is being used.