How do you allocate activity credits from an overhead cost center to a production cost center?

We allocate 100% of our overhead costs from our maintenance cost center to our production cost center(s).  We also receive labor activity credits (using activity MNTNOR) on the maintenance cost center due to plant maintenance work order labor confirmations.  We plan our maintenance cost center cost elements against an overhead activity type (named OVHD).  We allocate all of the primary costs using indirect activity allocations on activity type OVHD.

After we perform the actual activity allocation, there is a balance remaining equal to the total labor activity credits.

How do you get this credit balance to allocate?  The goal is to fully allocate the maintenance cost center.

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