taking an iPhone into a sauna for 20mins and not turning on

I took my iPhone XS Max into a sauna for about 25 minutes. The thermometer said 85 degrees. Now the screen is flashing yellow every ten seconds or so and the apple logo comes on and off. My phone began to work normally again for a few minutes, however, it then returned. When it turned on it told me that my face ID had been disabled for some reason and that I need to visit settings. By the time I opened settings, it shut off again. someone pls help!