The red screen tint on the Samsung Galaxy S8 is slowly being remedied via software update. The update is adding a setting for screen color balance, which should let you adjust the tint via software to get rid of the red tint. The keyword is should, as it may not help if there’s a serious hardware defect.
Though it has already hit a few models, the update is now rolling out to the AT&T model. If you own one, check for updates in Settings and let us know if you can fix the red tint on your screen!