@josephSabo: Are you using the official cable and plug adapter that came packaged with the phone? If so, do you see the Moisture Detected notification while connected to your charger, or does it appear randomly? To check for a possible issue with the USB port, please open the Samsung Members app > Get Help > Interactive Checks > USB, and follow the on screen prompts. Does this return any errors?
Have you tried clearing the cache/data of USBSettings? This will clear out any errors in the data that the phone is holding about the charging port. You can do this in Settings > Apps > 3 line menu (across from 'Your apps') > USBSettings > Clear cache > Clear data.
In that case, it may be best to get an engineer's opinion. You can take a look at your repair options here: https://www.samsung.com/uk/support/repair/
They'll be able to confirm for you if this is a hardware fault 🙂