In XFCE, how do I add bluetooth functionality in Nix OS?

Here's what I added/configured in my configuration.nix as suggested by Microsoft Copilot AI:

hardware.bluetooth.enable = true;

hardware.bluetooth.powerOnBoot = true;

services.blueman.enable = true;

hardware.pulseaudio.enable = true;

my nix configuration at github: https://github.com/doodstecsonhere/nix

After adding those to my config file, I get a Bluetooth GUI on the system tray which I can use to try and pair my bluetooth mouse and keyboard but my K480 Logitech keyboard doesn't show up in device search and pairing my Microsoft Sculpt Comfort Bluetooth Mouse results in an error, too.

I know the problem is somewhere within Nix OS and how I configure it 'coz these bluetooth devices work fine when pairing in a USB live environment of Linux Mint.

What am I doing wrong??? Helllp.