I’m using the Facebook Marketing API to pull ad performance data with level=account and level=campaign. When I include action_values in the fields parameter, it returns nothing, even though the same field works fine when I switch to level=adset or ad.

I remember this used to work at the account level in the past, so I’m wondering: Has this field been deprecated or restricted at higher levels? Is the absence due to a lack of support or simply no data?

I would appreciate any insight or updated documentation. Thanks!