New software update

No, but it's telling me that it's not a 2nd generation model (which doesn't support the new Magic Keyboard).

It is an iPad Pro 4th generation and yes, the new Magic Keyboard is supported by your model.

That said, read these support articles:--> Set up and use Magic Keyboard for iPad - Apple Support

and/or this one:--> If you can't connect your iPad to your Magic Keyboard, Smart Keyboard, or Smart Keyboard Folio - Apple Support

If the issue still persists, contact Apple Support using this link:--> https://getsupport.apple.com/?caller=kbase&SG=SG004&category_id=SC0300&symptom_id=20186

Regards

Giulio

Well, to my knowledge an iPad Pro 12.9" 2nd generation doesn't support the new Magic Keyboard (I mean this one: https://www.apple.com/shop/product/MXQU2LL/A/magic-keyboard-for-ipad-pro-129%E2%80%91inch-4th-generation-us-english?fnode=8d76cbc430a1f7c3b36639fc0263c3a295a2d9777f00536d1a1d265be27169fe30db9c4622a7600beb12a52bea18423c7d85dbe425d47d4596882778a18a94b2a75e400886c1366aa4cf62ec831a10a694a3f2f6b9a5577c28b79c3230ba3bba736b2ee30390986f8789da15ffd7c8ed

What Magic Keyboard are you referring to? This one?:--> Magic Keyboard - US English - Apple

No, you should find an "Axxxx" model number, as per this support article:--> Identify your iPad model - Apple Support

Regards

Giulio

Are you sure your iPad Pro 12.9" is a 2nd generation model?

What's the "Axxxx" code (where xxxx are four numbers) on the back cover of your device?

Giulio