Earlier today a family members iPhone 6 has some hot grease spilled on the screen. It was wiped off quickly, but now the screen has a dark area in the upper left part of the screen. The grease was about 300F. The front of the screen shows no damage at all and is still smooth as before. The dark area is clearly below the front. Attached is a picture of the screen. Any ideas on cause, and what to do next?