How To Fix MDC_BP_MODEL055 - Customer &1 already exists, provide valid external number

SAP Error Message - Details

• Message type: E = Error

• Message class: MDC_BP_MODEL - Business Partner Data Model

• Message number: 055

• Message text: Customer &1 already exists, provide valid external number

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message MDC_BP_MODEL055 - Customer &1 already exists, provide valid external number ?

  The SAP error message MDC_BP_MODEL055 indicates that there is an attempt to create a business partner (BP) with an external number that already exists in the system. This error typically occurs when you are trying to create a new customer or business partner using an external number that is already assigned to another business partner in the system.
  Cause:
  
  Duplicate External Number: The external number you are trying to assign to the new business partner is already in use by another existing business partner.
  Incorrect Data Entry: There may have been a mistake in entering the external number, leading to a conflict with an existing entry.
  Data Migration Issues: If data was migrated from another system, there may be duplicates in the external number assignments.
  
  Solution:
  
  
  Check Existing Business Partners: 
  
  Use transaction codes like BP (Business Partner) or SE16N (Data Browser) to search for the existing business partner using the external number you are trying to assign. 
  If you find an existing business partner with that external number, you will need to either use a different external number for the new business partner or update the existing one if appropriate.
  
  
  
  Use a Unique External Number: 
  
  When creating a new business partner, ensure that the external number you are assigning is unique and not already in use.
  
  
  
  Review Data Migration: 
  
  If this issue arises during data migration, review the data for duplicates and ensure that the external numbers are unique before importing them into SAP.
  
  
  
  Consult Documentation: 
  
  Refer to SAP documentation or help resources for guidelines on managing business partners and external number assignments.
  
  
  
  Contact SAP Support: 
  
  If you are unable to resolve the issue, consider reaching out to SAP support for further assistance.
  
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as BP for managing business partners, SE16N for data browsing, and MDC for master data configuration.
  Business Partner Roles: Understand the different roles that a business partner can have (e.g., customer, vendor) and how external numbers are assigned based on these roles.
  Data Consistency: Ensure that your data management practices maintain consistency and uniqueness of external identifiers to avoid such conflicts in the future.
  
  By following these steps, you should be able to resolve the MDC_BP_MODEL055 error and successfully create the business partner in SAP.