Message type: E = Error
Message class:  FKKFMCHK - Funds Management Checks/Derivations in FI-CA 
Message number: 054
Message text: Not possible to uniquely assign tax item to charge item
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The SAP error message FKKFMCHK054 indicates that the system is unable to uniquely assign a tax item to a charge item in the context of contract accounts receivable and payable (FI-CA). This typically occurs when there are multiple tax codes or tax items that could potentially apply to a single charge item, leading to ambiguity in the assignment. Causes: Multiple Tax Codes: There are multiple tax codes defined for the same charge item, and the system cannot determine which one to apply.
Configuration Issues: The tax configuration in the system may not be set up correctly, leading to conflicts in tax determination. Missing Tax Item: The required tax item may not be defined in the system for the specific charge item. Incorrect Master Data: The master data for the customer or the charge item may not be correctly maintained, leading to issues in tax assignment. Solutions: Review Tax Configuration: Check the tax configuration in the system to ensure
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