Use a really good tool, so you dont wreck the head/notch.
And like tegirinenashi wrote, try to heat the surrounding thread (mast) without getting the screw heated too much.
Gong actually has screws which dont get stuck that easy, compared to other brands earlier foils at least - where longer screws were used for the mast in particular.
How often do you take your foil apart?
Assume you are using TefGel or similar, as otherwise they wont last long....
If you dont manage to get it unstuck, leave it as it can still be used, you never need to take the baseplate apart anyways, right?
More difficult with the fuselage if you want to travel, otherwise it can also be left as is.
If you get a new one, remember the TefGel and still once a month take it apart, maybe relubricate just in case, to avoid it getting stuck.
Peter