I have two parts and after adjusting the dimensions, the sketch became underdefined and I have no idea which part of my sketch is screwed up. I have attached the two files separately.
When I had opened your file, it showed dangling relations of a point. You can check this by selecting "Display/Delete relations, and search for Dangling relations, although you should see brownish accents in your sketch, already indicating dangling relations.
A little more information would be helpful here. Why did you post two Parts? Are they both in an Assembly, and you're referencing one of them in the other one? If yes, that could account for the errors in your part 2. If that's the case, please Pack and Go the Assembly to a zip file and post it here.
If that's not the case, please explain further.
Delete this relation
and add this relation
Retrieving data ...