I have a campaign facet called Advertising Area (just like the one found in Google Ads). Within this facet,there are 2 levels of custom groups i.e. Country and Region and the last level is City:
Campaign facet : Advertising Area 1st level group - Australia 2nd level group - Victoria 3rd level tag - Melbourne
In a new campaign, I try to select "Australia" as a tag for a campaign facet but Sitecore prompts an error "Some of the fields in this item contain fatal errors".
Does it mean I can't use custom group as tag in campaign facet?