I had this problem before but didn't realize there was a plastic protective film over the factory installed screen protector. I removed it but kept the screen protector on and so far have zero issues with it. So my problems wasn't the screen protector but the extra protective film that was on top of the protector that is meant to be removed anyway.
Hey can you check something for me if you don't mind since you've removed the screen protector? My display seem to have a pink or green tint when tilting the phone slightly and viewing off an angle which is especially noticeable on a white background. Is such an issue present on your device? I'm wondering if this is caused by the protector but don't want to remove mine. I've decided to return mine if not the case.
Thanks for the reply. I have this problem whether dark mode is on or off and also no colour adjustments. I didn't have this issue with my S20 Ultra though so it's a bit strange.