Recently I've had issues charging my phone. It used to be that I had to put the plug into the phone in a particular way and it would begin charging. Now it won't charge at all while it is on and when I try to charge it while it is off, the battery screen shows up, then goes off and this repeats. It is charging, but at a very slow pace; so, for example, I left it off at 11 pm last night and when I checked it this morning, it had charged at around seventy percent. What do I do to fix this? Is it an issue with the port or what?