Your first problem is no primer. Without a primer base, your paint has nothing to bite to.
The clear plastic is a high gloss surface. Primer acts as rough surface giving the top paint coats something to grab on to. Since there's no primer base, the paint will just peel up everytime you paint over it.
There are a few things you can do. If you're going paint a layer to appear on the inside to replicate the interior color, use a flat color to do it. First, get a sanding stick with a very fine grit, like a polishing stick for fingernails. Buff the frame so that's a very slight haze. The rough texture will be enough to allow the paint to grip. Then paint the interior. Let that dry for at 48 hours. Then you can brush on your top gloss, exterior color. If you're not doing an interior color, brush on some Mr. Surfacer 1000, let that dry overnight or longer, then brush on your top coat.
After that's all done, you can seal it in with a quick dip in future.
-Fred