Hi chetannakar,
Welcome to Apple Support Communities.
It sounds like you're unable to charging your iPad Air, and you're seeing an alert that says the cable isn't certified. Take a look at the article linked below, which describes similar issues, and try running through the troubleshooting tips that it provides.
Charge your iPhone, iPad, and iPod touch - Apple Support
These alerts can appear for a few reasons: Your iOS device might have a dirty or damaged charging port, your charging accessory is defective, damaged, or non Apple-certified, or your USB charger isn't designed to charge devices.
Follow these steps:
- Remove any debris from the charging port on the bottom of your device.
- Restart your iOS device.
- Try a different USB cable or charger.
- Make sure that you have the latest version of iOS.
- Contact Apple Support to set up service.
Ciao.