Doors and Windows - Sticking Metal Door

I have an elderly customer with an entrance door that faces south/southwest. It receives quite a bit of direct sunlight during the day. It's a 3' wide metal door painted red with magnetic weatherstripping. When the door stays shut for several days, which is quite often, it becomes very difficult for the door to open. It's as though there's a seal that forms between the weatherstrip and the door. This becomes very difficult for the homeowner to deal with. I've tried applying WD40 along the weatherstrip and the door to eliminate any grip between the 2 surfaces. That worked for a few days. I also applied a teflon spray to both surfaces and that seemed to work better, but not permanently. Any suggestions on what can be done to make this door easy to open no matter what the situation?

Respectfully,

Handy Matt

Replace the magnetic weatherstripping with the q-lon type weatherstripping.

I didn't think of replacing the weatherstrip. It sounds like a good idea. Thank you.