Use proximity sensor on calls on Android
When calling using your phone as a phone (touching your ear and cheek), the Teams app does not leverage the proximity sensor, turning off the screen. What happens is that my ear and cheek keep pressing buttons on the screen. I'm using a OnePlus 6T device. I'm expecting this happens to other Android users as well.
Derek O'Harrow commented
I actually have the opposite issue on my Galaxy S8+
The proximity sensor turns the screen off anytime my hand goes near the phone, which is fine when just using voice, but when viewing shared content or just trying to use the phone to look at something else, is a real pain.