How to make my game go full screen on android? (Google Pixel XL 2

Hey guys, I can’t seem to achieve full screen on my new phone (Google Pixel XL 2). Other games are full screen but I seem to get a bar, I’ve tried 2880 x 1440 resolution and other resolutions but I feel like that area is locked. I’ve attached a screenshot that shows that black bar. Thanks in advanced!

24 hidden Android settings you should know about

Google Pixel 2 XL Review

Google Pixel 2 and Pixel 2 XL: Specs, features, FAQ, tips

Google Pixel 3a XL Review: The Best Phone Under $500

Pixel 2: How to change home screen

How to Change the Screen Resolution on Your Google Pixel Pro — And Why You Should « Pixel :: Gadget Hacks

Google Pixel 2: Price, Specs, and Release Date

Google Pixel XL review, price and battery life

Google Pixel 2 XL review: Google's supersized, bezel-less flagship