Recording audio through mixer to laptop

Hi,

I’m trying to record audio via a mixer to laptop. Even though we have backing track and microphone going through the mixer, only microphone is being picked up in audacity. Can anyone tell us where we might be going wrong?

Mixer is Behringer qx1204usb
Using windows 11

ETA

Just tried using music from a different source and only picked up vocals from a song from YouTube, no instrumental at all

Make sure Windows “enhancements” are turned OFF.

Thank you, this was indeed the issue Many thanks, I was ready for throwing the lot through the window!!!