If your iPad is not charging through the port, there are a few things you can try to fix it:
Check your charging cable: Sometimes the problem may be with the charging cable. Make sure that your charging cable is not frayed or damaged in any way. Try using a different cable to see if that solves the problem.
Clean the charging port: The charging port on your iPad can become clogged with dirt, lint or other debris, which can prevent it from charging properly. Use a toothbrush or a soft brush to gently clean the charging port. Be careful not to damage the port.
Restart your iPad: Sometimes a simple restart can fix the problem. Press and hold the power button until the "slide to power off" option appears. Slide the option to turn off your iPad, wait a few seconds, and then turn it back on.
Check the wall adapter: Sometimes the problem may be with the wall adapter. Try using a different adapter to see if that solves the problem.
Contact Apple support: If none of the above steps work, it may be a hardware issue. Contact Apple support or take your iPad to an Apple store for repair or replacement.