On the Magic Keyboard with Numeric Keypad, it might happen that the numeric keypad (numpad) doesn't work.

Ensure clear key = num lock is set in the user interface.

Press the clear or  key, that's the key below F16, and the Numeric Keypad should work again.

The clear key acts like the Num Lock key on Windows keyboards.

If this doesn't help, ensure that the Windows Mouse Keys Mouse Keys are turned off.

Note: NumLock can be turned on automatically in the menu: Settings > NumLock on app start..