How To Fix FMCA_BRF128 - Fields are not allowed to be entered twice

SAP Error Message - Details

• Message type: E = Error

• Message class: FMCA_BRF - FMCA -> BRF Interface

• Message number: 128

• Message text: Fields are not allowed to be entered twice

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message FMCA_BRF128 - Fields are not allowed to be entered twice ?

  The SAP error message FMCA_BRF128 indicates that certain fields in a Business Rule Framework (BRF) application are being entered multiple times, which is not allowed. This error typically arises in scenarios where the same input field is being referenced or used more than once in a decision table or rule set.
  Cause:
  
  Duplicate Field Entries: The most common cause of this error is that the same field is being defined or used multiple times in the same context, such as in a decision table or rule.
  Incorrect Configuration: There may be a misconfiguration in the BRF application where fields are not properly defined or are mistakenly duplicated.
  Data Model Issues: If the data model used in the BRF application has overlapping or duplicate definitions, it can lead to this error.
  
  Solution:
  
  Review Field Definitions: Check the decision table or rule set where the error occurs. Ensure that each field is defined only once. Remove any duplicate entries.
  Adjust Rule Logic: If the logic requires the same field to be evaluated multiple times, consider restructuring the rules or using different fields to achieve the desired outcome.
  Check Data Model: Review the data model associated with the BRF application to ensure that there are no overlapping definitions or duplicate fields.
  Testing: After making changes, test the BRF application to ensure that the error is resolved and that the logic behaves as expected.
  
  Related Information:
  
  BRF+ Documentation: Refer to the official SAP documentation for BRF+ for detailed guidelines on defining fields and rules.
  SAP Notes: Check for any relevant SAP Notes that may address known issues or provide additional guidance on handling this error.
  Community Forums: Engage with SAP community forums or support channels for insights from other users who may have encountered and resolved similar issues.
  
  By following these steps, you should be able to identify the cause of the FMCA_BRF128 error and implement a solution to resolve it.