Some keys not working on new magic keyboard
I recently bought a new iMac M4 with a magic keyboard and mouse and after a couple weeks had issues with some keys on the keyboard when putting in my password to unlock my screen. I called into Apple Support and they had me go into my Apple store. The tech did a couple things and all seemed ok until I got home and still had the same issue. I called Apple Support again and this time, the tech was able to fix my issue over the phone. It had to do with having the "mouse keys" turned "on". This is an accessibility function. I'm not sure how they got turned on to begin with, but what it does is make several keys on the keyboard to appear to not function correctly. Those non functioning keys were now operating the mouse movements. I read several community posts saying to hit the "option" button 5 times, supposedly turning the "mouse keys" option on and off. I tried that and it didn't work. There is also an option in settings to allow the user to hit "option" 5X, but that can be turned off, which I did. Today's solution was to hit "option" and "command" at the same time and then hit F5. A list pops up and my "mouse keys" was on! So I unchecked the box and all is right with the world once again. Yeah!
iMac 24″, macOS 15.3