Heya!
At the bottom right - right click the sound icon and click playback devices > Go to the sound window > look for Dolby Atmos and make sure it is properly installed
Is it located there and everything look correct? Let me know
If it is not in the list go to Device manager > sound, video, and game controllers > Dolby atmos > right click and click uninstall > remove the dolby device from your PC and restart