Phone charging

Follow the steps provided here:

If your iPhone, iPad, or iPod touch won't charge - Apple Support

If nothing helps, contact your nearest Apple Store and have your iphone inspected. They will give you all the available options.

Regards

Giulio

If it is defective, not damaged, and within the warranty period, they will likely replace it.

If you believe it to be defective, then make an appointment at the genius bar and have them evaluate it.