What can I do about main camera problems on the LG Viewty KU990?

I just bought this phone used off of ebay from an American seller and the seller posted that all the functions worked fine. I get it, turn it on, start testing it out, and when I try out the external camera (one of the main selling points of the phone) all I see are multi-colored (mostly pink) vertical lines. I can zoom in and out of them, change their scheme, like from black and white to inverted, and all that other stuff, but I can't get them to go away and actually take a picture of something. The camera on the face of the phone works perfectly. I'm wondering if there is a way to fix this or a person to send it to and if so, does anyone know how much it would cost or should I just try and return it. I really like this phone and if there is an easy fix, please let me know. Please keep in mind that I have tried everything I could, including messing with the ISO, and I just think that the camera may be broken.
Also, would completely resetting the phone lock it to one carrier? Which one would it be? I'm using T-Mobile right now and I've tried looking it up, but found nothing. I thought resetting it would maybe help fix the problem.