Here are some things to check why a user hasn't entered a Series

How long ago was it set live? (We check for entry rule matching once every hour or on ping.)

Check entry ruleset (Any glaring errors? Targeting a URL incorrectly, targeting visitors only and not users, etc.)

Check exit rules (Are people matching the exit criteria? They won’t enter if so.)

Compare to the same filters in their Contacts list - do users actually meet the criteria?

Is it an email only Series, and do they actually have an email address (is their email address bounced?)

@lisa b11​  - I am facing a similar issue since today morning where the users are not entering a series on a ping. Users are only entering the series when the hourly check happens. This is a problem for me because the First Run Experience of the app is part of the Series.

For more context: my series entry rule has two conditions - email should contain a particular domain and a custom attribute should be true. The custom attribute is updated async from the app through intercom(update) call. However, when the call is coming through the user is getting updated with the right value of the attribute (checked in user list) but the user is not entering the series till the next hourly sync happens.