Probably a lot of lint in there! My 4 year old phone gets that way until I clean it out with a plastic pick (very vigorously at that) and it's like new again.
Lint was only ever an issue with my Lightning connector iPhone. Unfortunately it wasn't the issue with the USB-C phones, the ports were just worn out.
Lint was only ever an issue with my Lightning connector iPhone. Unfortunately it wasn't the issue with the USB-C phones, the ports were just worn out.