"Hide Items with No Data" greyed out in Slicer Settings

[Sarahsodapop]

Hi All,

I'm using Excel for Mac, and am working on my budget. I've created a pivot chart with a slicer for my monthly categories, but would like for the categories with no values for the month selected to be removed from the slicer. I've googled a good bit, and tried unchecking "Hide Items with No Data" in the slicer settings, but it's greyed out. Does anyone have suggestions about why that isn't an option?

Thanks!

 

[Sarahsodapop]

https://imgur.com/zDdler2

I don't believe the screen shot showed up previously...