I have created a few traits and backfilled last 30 days data, and combined traits to create segments. However 24 hours later the traits and segments have no population, is there a lag between when trait/segment is created and when they start to populate?
Newly created traits start capturing audiences two to three hours after creation. However, due to the large volume of data that Audience Manager performs on a daily basis, the backfilled population is not immediately reflected in the Unique Trait Realizations and Total Trait Population graphs.
Audience Manager updates the Trait Graph with the backfilled population within 48 hours from trait creation.
So I would recommend giving it another day and see if you get some numbers in there. If you still don't see any numbers in there and you believe you should (it's a trait that should be capturing data and should have already been capturing data), then I recommend reaching out to Customer Care.