LCD Screen replacement

I had recently bought a LCD Screen from Paycheap, it came boxed with bubble wrap, I opened the screen and fitted the screen on and as I switched on the laptop it had a line running from the top to bottom, I sent a picture to them and they said it needed to be replaced. It's been over 2 weeks and they still said they trying they best and checking, I have no idea what they checking for because it's a fault on their side.