Message type: E = Error
Message class:  FKK_ID_BR - Message class for Brazil Withholding tax functionalities 
Message number: 303
Message text: Maintain Supplement Tax Code for Tax Rate &1
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The SAP error message FKK_ID_BR303 indicates that there is an issue with the configuration of the Supplement Tax Code for a specific tax rate in the SAP system. This error typically arises in the context of Brazil's tax regulations, particularly when dealing with the calculation of taxes in the SAP Convergent Charging or SAP Contract Accounts Receivable and Payable (FI-CA) modules.
Cause: The error occurs when the system cannot find a valid Supplement Tax Code for the specified tax rate (&1). This can happen due to several reasons: Missing Configuration: The Supplement Tax Code has not been maintained in the system for the specified tax rate. Incorrect Tax Rate: The tax rate being referenced may not be correctly defined or may not exist in the system. Data Inconsistency: There may be inconsistencies in the tax configuration data that prevent the system from processing the tax correctly.
Solution: To resolve the error, you can follow these steps: Check Tax
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