Is my replacement screen faulty?

My Iphone7 screen was cracked so I decided to replace the screen by myslef. I bought a supposedly “genuine” refurbished screen and did the replacement without too many complications but when I first tested the screen there were some artifacts (see photo). The artifacts seem to appear some seconds after the display is turned on and the touchscreen is only unresponsive over those parts of the screen. I reconnected the old screen to see if there was any damage done to the connectors during the replacement but It works completeley fine without any artifacts and the touchscreen is fully responsive.

Now I’ve checked the connectors of the screen and there is no obvious damage/dust on them, so I’m starting to think that the screen I got is faulty (maybe that’s why it was labeled as refurbished?).

My question is whether there is any other way to test if the screen is faulty or there is something else wrong.

Thanks in advance!