Phone won’t boot when Antenna Flex Plugged in.

Recently my iPhone 7 Plus started not booting up after a housing replacement, first I thought it was the housing it self so I put it back in the original. Still had the issue, then I started in plugging something this maybe something might of gone bad after moving it to another housing but nothing seems to help until I unplugged the antenna near the cameras, the one resting on top of the flash. I noticed that it also got really hot when I tried to boot the phone up . Any reasons?