Message type: E = Error
Message class:  KZ - Cost Object Repetitive Mfg / Process Mfg 
Message number: 029
Message text: You cannot save now because cost object & is being processed
The change you made to the master data also has to be transferred to
the master records of the cost object IDs lower down in the hierarchy.
The system cannot currently make these changes because the lower-level
cost object ID &V1& is being processed by user &V2&.
Wait for the other user to finish processing the cost object ID and
then save your changes again.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message KZ029, which states "You cannot save now because cost object & is being processed," typically occurs when you attempt to save a transaction that involves a cost object (such as a cost center, internal order, or project) that is currently being processed or locked by another transaction. This can happen in various modules, including Controlling (CO) and Project System (PS).
Cause: Locking Mechanism: SAP uses a locking mechanism to prevent data inconsistencies. If a cost object is being processed by another user or transaction, it will be locked, and you will receive this error when trying to save your changes. Background Jobs: Sometimes, background jobs or batch processes may be running that are using the cost object, causing it to be locked. Long-running Transactions: If a transaction takes a long time to complete, it may hold the lock on the cost object longer than expected.
Solution: Wait and Retry: If the cost
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