Quicktime Auto-Rotate Issue

I have an iPhone X and was trying to use my new MacBook Pro as a monitor because I film videos on my iPhone and would prefer to use the better rear camera instead of using the front-facing camera. My friend showed me how to do it on QuickTime, but whenever he rotated his phone, the Quicktime Player window would auto-rotate with it. Mine will not. I made sure the orientation wasn't locked and all that, but for some reason it works fine for him and refuses to work for me. I haven't been able to find a single answer for this issue as it seems like very very few people are experiencing it.