I've painted my front door but the paint is rubbing off when I wipe

If it was painted over the old paint without cleaning and sanding, there is not much you can do, as with the weather, any gloss or varnish would crack and peal away. Sand it, and paint again, must be wheater proof paint for outdoors.

Paint work shouldn't just wipe off during cleaning. Unfortunately it sounds as if the preparation wasn't done properly. I'd suggest sanding it all back and redoing it. I'd also suggest an adhesion primer if going over old gloss work. Also make sure whatever paint system you want to use is suitable for exterior application.

It all needs rubbing down and a Wethersfield exterior undercoat and gloss applying then you will have no problem

Dont use water based paint especially on exteriors. Its rubbish should never be sold.