I would suggest looking for a misconfiguration of route paths for your planning groups. For any planning group when you add route path associations, utilize the 'search' option (default) to add. The route paths that you can select for association will show the offered count over the past six weeks.
A route path (queue, language, skill set) is a way for you to describe what we query historically. If you've configured a route path that has no historical volume, we won't find any when we query analytics and obviously won't create any forecast volume for that route path.
Another caveat, and noted in resource articles and in the user interface itself, is "Agents must be able to handle all of the route paths in this planning group to be scheduled against any of the route paths in this planning group."
https://help.mypurecloud.com/articles/about-workforce-management/ - "Planning groups" section has a few articles that give more information
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Jay Langsford
VP, R&D
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