First thing I would do is check to see if another charger makes a difference. Next on the list would be make sure the port is free of debris. Give it a quick inspection using a flashlight and see if there is any lint or dust caught in the port. It's pretty common for there to be a layer of crud compressed into the back from being repeatedly forced into the port every time you put a charger in it. You can use a toothpick or something non conductive to gently (be mindful of the pins) clean it out.
But if you're still getting the same result after that, it sounds like the lightning port (charger port) might have been damaged in the incident. Depending on the sorts of issues you've have it could have already been borderline faulty anyways.