Message type: E = Error
Message class:  FKKID_WHT_MSG - Messages for WHT Loc. Cross-Country(FI-CA) 
Message number: 006
Message text: Tax suppl.for "Adjustment" is not defined
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The SAP error message FKKID_WHT_MSG006 indicates that there is an issue with the tax supplementary information for an adjustment in the context of the SAP Convergent Charging or SAP Contract Accounts Receivable and Payable (FI-CA) module. This error typically arises when the system is unable to find the necessary tax configuration for a specific adjustment transaction.
Cause: Missing Tax Configuration: The primary cause of this error is that the tax supplementary information for the adjustment type is not defined in the system. This could be due to: The adjustment type not being properly configured in the tax settings. The relevant tax codes or tax types not being assigned to the adjustment type. Changes in tax regulations that have not been updated in the system. Incorrect Transaction Type: The transaction type being used may not be set up to handle tax adjustments correctly. Data Inconsistencies: There may be inconsistencies in the master data or transaction data that prevent
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