The screws holding the lightning port in are not unscrewing

They looked slightly rounded off, I would try a slightly larger phillips head and slowly turn with firm pressure, if they’re still not budging it’s difficult to get out, I would then try covering the screwdriver with thin rubber, like a rubber band, then firmly turning, the rubber helps fill the gaps and get more grip, if this doesn’t work drilling out is my last option, it will create a new groove and pull the screw out.