Message type: E = Error
Message class:  FAGL_ITAXBUPLA - Messages for Commercial Business 
Message number: 020
Message text: The valid-from date must not be after the valid-to date
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The SAP error message FAGL_ITAXBUPLA020 indicates that there is an issue with the date range specified for a tax-related transaction or configuration. Specifically, the error states that the "valid-from date" must not be after the "valid-to date." This typically occurs in scenarios involving tax codes, tax rates, or other date-sensitive configurations in the SAP system.
Cause: Incorrect Date Entry: The most common cause is that the user has entered a valid-from date that is later than the valid-to date in a configuration or transaction. Data Migration Issues: If data has been migrated from another system, there may be inconsistencies in the date ranges. Configuration Errors: In the tax configuration settings, the date ranges for tax codes or rates may have been set incorrectly.
Solution: Check Date Entries: Review the entries for the valid-from and valid-to dates in the relevant transaction or configuration screen. Ensure that the valid-from date is earlier than or equal to the valid-to
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