iPhone7+ Charger Port

I had my iPhone7+ plugged in this morning, and then when I went to plug it in again tonight it will not stay in the plug port on the phone. I tried a new plug, and got the same result. I gently wiped out the port to ensure there was not lint blocking the port. There was not and so that did not solve the issue. It seems like something is broken INSIDE the plug port on the phone. My Apple care ran out last month (of course) so wondering if there are any troubleshooting ideas before I take it in to an Apple Store for costly repair.