Hi, Lisa. One of the problems with working with oak or mahogany is the large pores. There are products made specially to fill them but they will not work as overall wood fillers, like the Minwax 2 part filler. One of these that does work for this is Bartley Paste Wood Filler. This is available at Woodcraft, who has retail locations in large cities, sells by mail order and, I believe, has a web site. Just apply it per label directions and be sure you have real burlap from a fabric store available. This will get down in the pores and hide that remaining paint. At the same time, it will give you a much smoother surface for finishing. They make a "light" and a "dark" color and you will probably want the "dark".