Users Not able to add additional approvers in Approver list generated by approval rules - Redwood

Summary:

Users are trying to add the Approvers in the Requisition approver list generated on redwood Page.

Steps below:

Before Requisition submission for approval, go to View approvers and select any approver from the list generated (Preapproval Hier)

Now click on +Add approvers button, Message will come up to add any approver in list.

We have option to Add 'Above current Participant' or 'Below current Participant'

Getting the message as below-

We can't Assign approvers to this Requisition right now.

This is happening to few users and based on initial investigation anyone having contingent Custom role is getting issue.

User having employee role are able to add the approver