Catalina & Magic Keyboard issue

I recently got a bluetooth magic keyboard for a 2013 imac 27" with Catalina. It works fine but I noticed that the brightnesss, search, volume, & lock key don't work. The function keys are working & when I run the accessibility keyboard applet it shows they are registering (being pressed) but they are not performing the functions they should. When I put my old wired keyboard on those keys work. Yes, I paired it with my 2019 macbook pro & it works so I guess there is some setting or Apple should clearly state on their website that it is not fully compatible with Catalina. Any help is greatly appreciated.