[ubuntu] Problems pairing iMac wireless keyboard and trackpad - Ubuntu 20.04 LTS on iMac 27, 2

I have installed Ubuntu Desktop 20.04 LTS on an Apple iMac 27(2011).

Struggling with pairing the Mac wireless keyboard and trackpad.

Possible to pair the keyboard, but doesn't respond after.

Trackpad not possible to pair - a bit tricky to enter numeric pairing code on the trackpad...

Anyone knows how to resolve this?

Thanks