Why is my phone not charging?
Why is my iPhone not charging?
Question marked as
Top-ranking reply
Force restart iPhone – Apple Support (UK)
Then try other genuine cable and another charger brick.
If no better you should arrange a repair
iPhone Service & Repair - Apple Support
Or
Contact - Official Apple Support
Anything other than Screen or Battery may be a replacement phone and the price is in the article under "Other damage"
See also: Get your iPhone, iPad, or iPod touch ready for service - Apple Support