So I was staining and polyurethaning my woodwork for the first time. I didn't notice until everything tried that I had a huge blob of polyurethane on my pine window Cill. I tried sanding it out. Eventually I got the blob off but it took the stain with it. I tried sanding and staining back over it but the stain would not take. I also tried using a stripping agent, sanding, wood conditioning and staining again. Still the stain wipes off completely back to the natural wood. HELP! Now I have a white blob on my window cill!