Message type: E = Error
Message class:  FICUSTOM - Customizable Messages for Funds Management 
Message number: 021
Message text: The revenue type selected is not an additional revenue type
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The SAP error message FICUSTOM021 indicates that the revenue type selected in a transaction is not recognized as an additional revenue type. This typically occurs in the context of revenue recognition or billing processes within SAP, particularly in modules like SAP Revenue Accounting and Reporting (RAR) or SAP Contract Accounts Receivable and Payable (FI-CA).
Cause: Incorrect Configuration: The revenue type you are trying to use may not be configured correctly in the system. It might not be set up as an additional revenue type in the relevant customizing settings. Data Entry Error: The revenue type selected in the transaction might be incorrect or not intended for the specific process you are executing. Missing Authorizations: The user may not have the necessary authorizations to use the selected revenue type. Business Rules: The business rules defined in the system may restrict the use of certain revenue types based on the context of the transaction.
Solution: Check Configuration: Go to the
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