Phone is not charging

This is a very broad question that could have many different solutions. The first step would be to look into the charge port and see if there's any lint or debris that would prevent the cable from making a secure connection. If the port is clean, then you may have either a bad cable, wall block, or charging port on the device. I would suggest switching out the cable and wall block before taking the phone to a repair shop or attempting a charging port replacement.