iPad does not see Smart Keyboard

Remove the Smart (folio) keyboard from your iPad - and carefully/gently clean the smart connector contacts on both the iPad and keyboard with a soft pencil eraser. Ensure that the contacts are dirt and dust free - and all debris from the eraser have been removed - before reconnecting the two.

If you can't connect your iPad to your Magic Keyboard, Smart Keyboard, or Smart Keyboard Folio - Apple Support

Do you perhaps see an error when connecting your Smart keyboard?

If you see an ‘Accessory may not be supported’ alert - Apple Support

If you are using a Smart (folio) keyboard, this alert is typical of a faulty folio keyboard. The electrical connections that pass though the flexible fabric hinges typically fracture - this usually resulting in errors and/or the on-screen notification that you see. 

The Smart folio keyboard itself is not repairable. The only remedy is replacement of the keyboard. As you appear to be within your one-year limited warranty, you need to contact Apple Support or your retailer.

You will find the Get Support link at top-right of this page. 

Alternatively, you can initiate a support case using the excellent Apple Support App. If not already installed on your device, the App can be downloaded from the App Store:

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

A further alternative is to visit the Genius Bar at your local Apple Store, where the technicians will be delighted to assist. When visiting the Genius Bar, a reservation is recommended:

Genius Bar Reservation and Apple Support Options - Apple (UK)