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The Charge Account is always aRequired field if the Service Catalog for the selected Service is "Billable". The GLA picker is restricted by the owner's GLA permissions. The owner is restricted by the logged in user. If the logged in user is not a coordinator, the user becomes the contact owner. Otherwise, the user has access to both the contact and department pickers.
For more information on how the Department Hierarchy or a Contact's association affects GLA permissions, please see the Department Hierarchy and People page.
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