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Why isn’t my segment collecting members?
There aren't any cookies in the segment. Follow the steps below to find out why:
Go to the "Inventory" tab, click "Audience segments", and select the troublesome segment.
Is the segment active?
Check the "Content association" section. Is the segment associated with at least one ad unit or placement? If the segment is targeting key-values, it must also target an ad unit or placement.
Have the page views and recency goals been met yet?
Are memberships expiring too quickly? Try setting a looser expiration period.