right side of screen wakes before the rest of the screen

Iphone 7 32gb model bought in december 2017 through tbaytel. after a couple months with the phone i noticed that sometimes when waking the phone up the right side of the screen will turn on before the rest of the screen does. it happens randomly, doesnt matter where i am, the weather, temperature, it just does it when it feels like. also last night i noticed when opening apps from scratch that werent already pre-loaded in the multi tasker, i had a line on the right side of the screen, as well as one on the left, which would go away once the app had finished loading. Im just looking for a general idea as to whats wrong, if warranty would cover it. etc, phones never been unresponsive to touch, this has been the only issue so far. I have linked a dropbox video showing the issue in action as well as a picture of what the lockscreen should look like.https://www.dropbox.com/sh/znpqa9zx5e9dd...