Anna Marie:  There are a couple of things you can do to get that bottom crust properly baked. The first (easier) one is to put your pie plate on a metal baking sheet when baking. This helps direct more heat to the bottom of the pie dish so the pie dough there will bake a little faster. If that doesn’t do it, try par-baking the bottom crust before filling it.  Once the dough is fitted in the pie dish, prick it all over with the tines of a fork, then bake for maybe 10 or 12 minutes, until the dough starts to firm up. Check it frequently, and if the dough starts to puff up, gently press it back down with a spatula or back of  a spoon.  When the dough has firmed up and is JUST starting to color, fill the pie shell with your filling and bake as usual. (But check the pie while it’s baking; if the edge begins to brown too quickly, carefully cover just the edge with strips of foil and continue baking.)