3231594 - Error "Project is locked by another user" when assigning a WBS element to sales order

When multiple people are creating sales orders and trying to assign the same WBS element to their documents, the error "Project is locked by another user" is raised.

SAP S/4HANA Cloud Public Edition

This message occurs The message when a project object (such as a WBS element) is currently being accessed or edited by another user, or possibly even by the same user in a different session or browser tab. It's due to the enqueue (locking) mechanism that ensures only one user or process can change a particular object at a time to maintain data consistency and prevent overwrites.

There are a few possible causes:

• Another user is actively working on or has an open session editing the same project.
• The same user has opened the same project in multiple sessions or browser tabs.
• A previous session did not close cleanly, leaving a lock (for example, closing a browser without logging out).
• An integration or interface (such as an API, background job, or technical user) is updating the project at the same time you attempt your action
• Persistance of WBS Elements ( Table PRPS ) holds fields for the assignment to a sales order item, thus saving a sales order iwth assigned WBS elements also needs to update the WBS master data table. 
• There are WBS elements which can be assigned only to one sales order item and not multiple items. 
• It was required that Users assigning a WBS to a sales order item immediately get informed if the WBS is currently used in other sessions. A locking error during sales order was considered are "not sufficient" in this process. 
• Thus, EPPM does an early locking already after the initial assignment to a sales order item within their API. 

Ensure only one user is changing the same project object (WBS element) at the same time

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