iCloud folder is empty on my Mac, but not my iPhone

Hi.

I have an iCloud folder that appears empty on my Mac. It should not be empty. When I search in Finder for the files that should be in it, they appear in the search and in the file path bar at the bottom. But clicking the folder in the search brings it up empty. However, when I double click the files in the search, which are audio files, they play. ...but the folder still appears empty.

When I look in the folder on my iPhone all the files are there.

I have tried copying the folder out of iCloud onto the Mac and just the folder copies with no files in it. And I've tried downloading the folder out of iCloud, and it takes a while, longer than an empty folder should, but it just ends up empty.

I'm not too worried about it, because the files are still there on my phone and I can transfer them to my Mac, but it's pretty dodgy and a nuisance and I would like to know what gives!

Anyone have any idea? Thanks.