My iPad Air won’t charge

These support pages should help with troubleshooting battery and charging issues:

Charge and monitor the iPad battery - Apple Support

If your iPad won't charge – Apple Support

Troubleshooting generally requires substitution of the Power Adapter and cable for another known-good item. Most models of iPad require a Power Adapter rated at 12W or greater to reliably charge. 5W Power Adapters intended for older models of iPhone are inadequate to charge an iPad; if the iPad charges at all, charging will be very slow.

Be aware that many computer USB ports cannot source sufficient power to charge an iPad. Unless explicitly designed for charging connected devices, computer USB ports are typically limited to 0.5-1A @5V (i.e., 2.5-5.0W).

If you continue to experience difficulties when using an appropriate Power Adapter of 12W or greater, you might be best advised to seek assistance directly from from Apple Support - and request a remote diagnostic test. You can contact the Support Team using the Support link at top-right or bottom-left of this page. Alternatively and perhaps easier, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/gb/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to test and assess your iPad, Power Adapter and cable(s):

Genius Bar Reservation and Apple Support Options - Apple

Maybe, maybe not.

the first troubleshooting steps is to try another outlet, power brick and cable, in various combinations.

it’s easy to confuse a phone level charger with an ipad charger and since phones only put out half the power an ipad wants you can end up with a charging block that the cable fits into that doesn’t give the ipad the amount of power it needs. There can also be cables that are not capable of carrying the iPad’s power demands.

You can also give your ipad a reboot and see if that helps.

And also take a peek in the charging port. As silly as it sounds, a bit of lint can impair charging.

If you go through all that and the ipad still will not charge it could be possible that its battery is reaching the end of its life. They do only have a finite number of charge cycles until they lose their ability to accept more power. In that case, if your ipad is an early version Air you may be money ahead to simply replace it. Battery replacements run around $100 and it just may not be worth it to spend that much on a years old device.

Charge the iPad battery - Apple Support

If your iPad won't charge - Apple Support

There are tips there and I believe a link to investigate service if you decide to go that route