Message type: E = Error
Message class:  UBB_CHANGE - UBB change processes im UIU 
Message number: 012
Message text: Change process not executable because usage contract is not active
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The SAP error message UBB_CHANGE012 indicates that a change process cannot be executed because the usage contract associated with it is not active. This typically occurs in the context of SAP's contract management or procurement modules, where usage contracts are used to manage agreements with vendors or customers.
Cause: The primary cause of this error is that the usage contract you are trying to modify or process is in an inactive state. This can happen for several reasons: The contract has been set to inactive manually. The contract has expired or is no longer valid. There may be a configuration issue or a missing status update in the contract lifecycle.
Solution: To resolve this error, you can take the following steps: Check Contract Status: Navigate to the contract in question using the appropriate transaction code (e.g., ME33K for display contract). Verify the status of the contract. If it is inactive, you will need to reactivate it. Reactivate the Contract: If the contract
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