Hey!
Are you plugging this USB-C cord into a wall outlet, a car, or another device? If it is plugged into another device, you may have to approve of this device before it can be allowed to charge the device. You can also try cleaning out the USB-C port. Likewise, make sure the USB charging brick is from APPLE - this is a common issue, and other bricks may not work with iPhone due to wattage issues. This may sound silly, but you can also make sure the outlet you are plugged into functions properly, and that whatever source you are using to charge has a high-enough output. You can also try to force restart the phone to see if that fixes the issue:
- Press and quickly release volume up button
- Then immediately press and quickly release volume down button
- Then immediately press and KEEP HOLDING the side power button. KEEP HOLDING it past the swipe to power off and KEEP holding it until you see the Apple Logo, then let go
Phone 15 Pro not charging - Apple Community - users in this thread have also suggested that their brick was causing the issue.
Best of luck,
Bryce