If it's not inserting all the way, it sounds like you've probably got some deeply embedded fluff/pocket lint in there, USBC ports are prone to this, they're not tough to clean but if you're not feeling confident about it, it may be better to take it to a professional.
If it IS inserting all the way, and the port feels loose, then it may need replacing. In which case the advice will depend on when and where you got your iPhone.
