No Approvers found. ORA-20240: An invalid approver has been encountered while processing the action

Hi,

Has anyone came across the below error before? This occurs in both FND Log and  PO Approval Analyzer output.

"No Approvers found. ORA-20240: An invalid approver has been encountered while processing the action type hr position level. Please verify the setup and approvers used in current action type. Invalid approvers originating system POS and originating system ID 2360191. " 

The issue is a user tries to submit a shopping cart for approval in iProc but following errors are received "Approval List could not be generated. Please contact your System Administrator to review AME rules setup"  "You do not have the authority to approve this requisition and an Approval List was not created automatically. Please contact your system administrator". We are using poistion hierarchy and I have checked that the requester is valid under the approver, approval groups are valid and assigned to the approver and also that FND User is assigned to the HR record. I ran then FND Debug and PO Approval Analyzer which is where the ORA-20240 error appeared.