Phone Thinks It's Charging When Not Plugged In. Everything works except the phone charging indicator stays on even after the phone is fully charged and Ive removed the USB cable. Does anyone have any suggestions of what could be causing it.

Yes its safe to leave your smartphone plugged into the charger overnight. Quite often my phone lights up the charging symbol even if the phone isnt charging. It says x hours until charged at the bottom and has the lighting on the battery at the top.
Many times the iOS issues including the charging issues automatically get fixed by just force restarting your device.
You may also like this. Actually it has been my experience that it does hinder charging and phone use. It charges when its plugged in but t. Battery is eaten up quickly at this point.

