Remove the Lightning connector assembly.

Before installing or replacing the Lightning connector assembly:

Remove any remaining adhesive, and clean the glued areas with isopropyl alcohol and a lint-free cloth.

Before removing the adhesive backing on a new assembly, make sure the Lightning connector assembly is correctly positioned by aligning the hole in the flex cable with the screw post. If the cable is misaligned, you won't be able to reconnect it to the logic board.