Screen double image. Ghost icons

So I replaced my iPhone 6 screen back in march. I noticed in July that when my phone starts to get warm it creates duplicate images of the icons under the icons. Almost like a ghost image below. I figured maybe one of the connections got loose so I opened it back up and made sure everything was secured. This only tends to happen if the phone is being used or warm. Has anyone else had this problem before? Any solutions on how to fix this issue or is the screen maybe faulty?