Cost center and job level approvals Expenses Workflow rules are not working as expected.

Summary:
Hi All,

The cost center and job level approvals are not working when the employee submitted expenses showing the following error message.
Cost center approval is getting the below error message
Error in evaluating routing slip due to user {username_from_fault_payload} being invalid or this user not having a valid manager.

Job level approval is getting the below error message. 
The request operation failed with the business rules defined for CostCenterRuleSet.

Can you please check the issues.

Please find the attached document for reference

Thanks,
Prasanth K.

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