Iphone XR getting really hot at the bottom of the screen

So this is my second iPhone XR with this problem. I had to swap the first for the same issue. It is getting really hot at the bottom of the screen just scrolling through social media and it is not event charging. But it is most noticeable after watching a couple of videos, which I like to do on my phone. Is it a common thing? Do all the Iphone XR overheat in that area? When i went to the apple store the guys there told me it wasn’t normal. The guy felt the bottom portion of the phone and also thought it was pretty hot and he swapped it. It is literally as if I was playing a game on my 6s, that’s how hot it gets just scrolling through social media. I checked the component list and there isn’t anything in particular in that area apart from the haptic motor and the speakers. Needless to say, this is a very, VERY, annoying problem for a phone I paid $1000 CAD.