How to change PO Approver?

Summary

Need to locate where PO Approver user is saved so it may be changed to a different user.

Content

The user responsible for approving Purchase Orders (our Procurement dept director) needs to be changed to a different user. When we implemented in 2017, the user was set within BPM Worklist -> Approval Groups -> PO Manager Approver, however, I do not see the PO Manager Approver group in 21B. I see PO Delegated Approver and Purchasing Manager Approval Groups. Does anyone know where I change the PO Approver?

Thank you!

Version

21B