Why did my ZTE Axon Pro stop taking touch input in the top left corner of the screen?

[AC Question]

It was the ZTE Axon Pro and while I was able to see through the dev toggle that the screen registered the touches in that top left corner (think of the back prompt for a lot of apps). It just wasn't going back.

And yeah, I know that the back button on the nav bar makes it obsolete, but it's irksome and who knows? Maybe I might need it someday.

 

[srkmagnus]

Do you know if you dropped the phone? That could attribute to damage on the panel resulting in the non-responsive parts of the screen.