Israel, It sounds like it is a bad screen. Check to see if the connectors are bent in any way. Every once in a while some replacement screens are just DOA when they arrive. Hopefully whoever you bought it from will send you a replacement.
The other thing that I encounter a lot is the frame will be dented and cause the screen to sit high. I would check it carefully and make sure nothing is pushed in. If it is I just take a screwdriver and a rubber mallet and pound it out