2824240 - No users available in People picker in Manage workflow application

• When using the 'Manage Workflows for Purchase Orders' app to create a new flexible workflow entry and creating a new workflow step.In the Recipients step, it is not possible to select any users using the value help option.
• The approvers don't see all details of the approval task.
• The People Picker dialog box does not display any users.
• No users available in manage workflows for purchase order application.
• No users available in manage workflows for purchase requisition application.
• No users available in manage workflows for purchase contract application.
• No users available in manage workflows for supplier invoice application.
• No users available in manage workflows for Service entry sheet application.

SAP S/4HANA Cloud Public Edition

1. Open the Manage Workflows for Purchase Orders app.
2. Click the Create button.
3. In the Workflow Name field, enter the name of workflow.
4. In the Steps are, click the Create button to add a new workflow step.
5. Choose Add to simulate the creation of a new workflow entry.
6. In the Header area, select Release of Purchase Order in the Step Type field.
7. In the Recipients area, select User in the Assignment By field.
8. In the Recipients area, click the People Picker button in the User field.
   The Select: People Picker for Purchase Order Approver dialog box opens.
9. In the dialog box, click the Go button.
   No users are found. 

1.Missing role to approve the purchasing document

and/or

2.Missing work agreement

1.Create a custom business role by copying "Manager (SAP_BR_MANAGER)" or "Purchasing Manager (SAP_BR_PURCHASING_MANAGER)" or 'Purchaser (SAP_BR_Purchaser)

And this role has to be assigned to all users that are to be enabled as PO approvers.

You may add below business catalogs related to approval to your roles

Examples catalogs are given below:

• SAP_MM_BC_PO_WIAPPROVE_PC      is for PO
• SAP_MM_BC_PR_WIAPPROVE_PC      is for PR
• SAP_MM_BC_SES_WIAPPROVE_PC    is for SES
• SAP_MM_BC_INV_WIAPPROVE_PC     is for Invoice

Refer below help document for catalogs related to Various documents

Working with Purchase Orders in My Inbox | SAP Help Portal

Search for any documents help document in above link in search space 'Working with * in My Inbox'

For example, search with 'Working with contracts in 'My Inbox' App you will get results 'Working with Purchase Contracts in My Inbox'

2.Create a valid work agreement for the worker(approver/user) with proper Validity.

and to avoid error with approval recipient roles also maintain manager details through the app "Manage Workforce"

SAP_BR_MANAGER, SAP_BR_PURCHASING_MANAGER, SAP_BR_PROJ_MANAGE_COMM, S_POUsersToAuthProfile, S_MMPURWorkflowVH_CDS, M_BEST_EKO, People Picker, Recipient, Workflow, SAP_MM_BC_PO_WIAPPROVE_PC,Workflow Access, My Inbox access,Approver,Not Found,Not Available,cannot find,Not exist,Not Visible,Not selectable,cannot select,SAP_MM_BC_INV_WIAPPROVE_PC,supplier invoice  , KBA , MM-FIO-PUR-PO-2CL , Fiori UI for Purchase Orders (Public Cloud) , MM-PUR-GF-WOF , Workflow , MM-FIO-PUR-PO , Fiori UI for Purchase Orders , MM-FIO-IV-2CL , Fiori UI for Invoice Verification (Public Cloud) , How To