Charging shuts down - says moisture detected

Hello ~ Take a look here:

Water and other liquid damage to iPhone or iPod isn't covered ...

As others have recommended take it in for a check:

Genius Bar Reservation and Apple Support Options

~Katana-San~

Do take the phone to have Apple examine it; unfortunately, the regular hardware warranty does not cover damage caused by liquids. See the terms here

Legal - iOS Warranty Document Us - Apple

If you purchased Applecare +, it should be covered

Legal - AppleCare+ - Apple

Also check if the charger end been in contact with liquid.

I recommend you bring the phone to an Apple Store or authorized service center. They will be able to confirm the problem and, hopefully, address it under warranty.

As recommended, take it to Apple. We - all other users - cannot check it. Is it in a humid environment?