How do I fix my trim that wasn’t sanded well
I'll take a different tack and assume you're referring to the bumps where the fastener holes were patched. My fix at this point would be to make sure that the paint is thoroughly dry so that it sands well. Then take a random orbit sander and go over those areas again. If you tilt the sander just slightly so as to apply pressure on one edge of the pad  you can sand a fairly small area fairly quickly. You'll have to completely repaint, of course, including any primer coat you may have done before.