Mixer and audacity

I have this xenyx 1204 usb mixer and ive installed all recent drivers for it.
im getting sound out of pc into my mixer via usb and back out to my monitors.

but when i try recording the sound out of my mixer into audacity . im not getting any sound

You’re not getting the bouncing red meters and blue waves on the timeline, or you can’t hear it while recording? They’re different. Koz