Credit Memo workflow error with AME invalid collector in 12.1.3

Hi All,

Error:-  Dispute created in Adv.Collections. Workflow is erroring with invalid collector.

Test Case:-

1.Collector exist at Customer account and site Level.

2.Collector has approval limit for credit memo.

3.Collector is defined as employee and has collection agent as role in CRM and is visible in collection universal work queue.

4.Created a dispute for amount 2USD for 40 total txn.amount

    Please guide me the AME steps or any setups in AR am I missing.

Workflow Error:-