Personally, I use a brush when painting wood, especially cabinets. (I'm assuming you're painting wood.) You can try a couple of things.
You can just sand with a fine-grain sandpaper the area in question, and repaint. If that doesn't look right, sand the entire surface that has the problem, and repaint. Of course, a brush should take care of problem all together.
As an aside, moisture underneath that expands will cause paint to bubble. It occurs between the finished surface and the surface immediately below. (It may be between 2 layers of paint or between a primer and the surface being primed.) This occurs where there are joints or ends.
Start with the spot-sanding and painting and work your way from there. My best to ya and hope this helps.