iPhone 6S Lightning cable not staying in

I have an iPhone 6S and have been having an issue with it charging for a few months now. When I plug it in to charge, the lightning cable doesn't stay in, causing it to fall out, or not even charge the phone. The phone charges though when it is connected a certain way with minimal movement. It does this with different chargers, so it's not a problem with mine. So what do you recommend doing? Possibly getting a new phone? Or can Apple replace the charging port?