There may also be debris stuck inside the charging port. If when you plug in the charging cable and the piece sticks out slightly, that may be your problem. Very gently take something thin, like a paperclip, and move it left and right in the port. Keep the paperclip close to the top (the screen side of the phone) to avoid damaging any of the connectors, and see if you can pull out some dust or lint from being in your pocket so long. You'd be surprised at how common this situation is.