Message type: E = Error
Message class:  FKKINV - Invoicing in Contract Accounts Receivable and Payable 
Message number: 077
Message text: Invoicing is not active yet
In table <LS>TFK000C</>, the <DS:DE.XINVA_KK>Invoicing Is Active
</> indicator is not selected.
Functions that need Invoicing to be active cannot be performed.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FKKINV077 indicates that invoicing is not yet active for the specified business partner or contract. This error typically occurs in the context of SAP Convergent Charging or SAP Contract Accounts Receivable and Payable (FI-CA) when trying to create an invoice for a business partner or contract that has not been fully set up for invoicing.
Cause: Invoicing Not Activated: The invoicing process for the business partner or contract has not been activated in the system. Incorrect Status: The status of the contract or business partner may not allow for invoicing (e.g., it may be in a draft or inactive state).
Configuration Issues: There may be configuration settings in the system that prevent invoicing from being activated. Missing Data: Required data for invoicing may be missing or incomplete.
Solution: Activate Invoicing: Check the status of the business partner or contract in the system. If invoicing is not activated, you may need to activate it through the
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