Manage Receivables Specialist Assignment Rules

Summary: We are looking to configure the receivables specialist assignment rules to further support our reporting and analysis of unapplied receipts.

Content (required): When going to the manage receivables specialist assignment rules configuration, I am able to create the conditions, but the 'Assign Receivables Specialist: Set Value to drop down is blank" Can someone help guide me to how I would populate users in this area to assign?

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