Just purchased a Magic Keyboard with neumeric keypad. It is recognized my IMac, but the number key pad is not working. I am macOS Monterey

Which Magic Keyboard? The one with touch ID or without?

The one with Touch ID has to be one of these…

Mac Models

• MacBook Air (M1, 2020)
• MacBook Pro (14-inch, 2021)
• MacBook Pro (16-inch, 2021)
• MacBook Pro (13-inch, M1, 2020)
• iMac (24-inch, M1, 2021)
• Mac mini (M1, 2020)

If a numeric keypad doesn’t work on Mac - Apple Support

I have this issue as well. Apple's own wireless keyboards and trackpads DO NOT work well in MacOS Monterey. For the trackpad, you can sometimes get it to work if you constantly restart Finder. I haven't found a solution that gets the keyboard to work. The keyboard seems to get discovered by Bluetooth a little better if disconnected from USB. The issue seems to be that Monterey cannot accurately differentiate an extended Apple keyboard from a normal (no keypad) Apple keyboard. Efforts to manually adjust the keyboard (from normal to extended) in Settings also does not work.

FWIW, the keyboard works as a wired keyboard when the charging cable is plugged in so there is no need for it to be discovered by Bluetooth. Personally I never use my extended keyboard in wireless mode so I have no issue. I haven't tested it in wireless mode to see if there's is a problem, I will at some point today.

Alas. Same issue in wired and wireless. Monterey simply cannot detect the extended keyboard - even after all of the usual restarts, resets, etc. Issue has existed since buying the new Mac M1 Mini and Apple extended keyboard (w/ fingerprint sensor) several weeks ago. Everything out-of-the-box new and Monterey is still a FAIL.

I see. Well I don't have any extended or non-extended Magic Keyboards with fingerprint sensors. Perhaps that's the issue. I can't check that.