How To Fix MDC_BP_MODEL057 - Customer number &1 is already assigned to business partner &2

SAP Error Message - Details

• Message type: E = Error

• Message class: MDC_BP_MODEL - Business Partner Data Model

• Message number: 057

• Message text: Customer number &1 is already assigned to business partner &2

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message MDC_BP_MODEL057 - Customer number &1 is already assigned to business partner &2 ?

  The SAP error message MDC_BP_MODEL057 indicates that a customer number (represented by &1) is already assigned to a business partner (represented by &2). This typically occurs when there is an attempt to assign a customer number to a business partner that is already in use by another business partner in the system.
  Cause:
  
  Duplicate Assignment: The customer number you are trying to assign is already linked to another business partner.
  Data Migration Issues: If you are migrating data from another system or performing mass uploads, there may be conflicts in customer number assignments.
  Incorrect Business Partner Configuration: The business partner may not be set up correctly, leading to conflicts in customer number assignments.
  
  Solution:
  
  
  Check Existing Assignments: 
  
  Use transaction codes like BP (Business Partner) or SE16N (Data Browser) to check the existing assignments of the customer number in question.
  Look for the business partner that is currently using the customer number.
  
  
  
  Reassign Customer Number:
  
  If the customer number is indeed assigned to another business partner and you need to reassign it, you may need to unassign it from the current business partner first.
  This can be done by navigating to the business partner in question and removing the customer number assignment.
  
  
  
  Use a Different Customer Number:
  
  If the customer number is already in use and cannot be unassigned, consider using a different customer number for the new business partner.
  
  
  
  Data Migration Review:
  
  If this error arises during data migration, review the data being imported to ensure there are no duplicates in customer numbers.
  
  
  
  Consult Documentation:
  
  Refer to SAP documentation or help resources for specific instructions on managing business partner assignments and customer numbers.
  
  
  
  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.
  SAP Notes: Check SAP Notes for any known issues or patches related to business partner management and customer number assignments.
  User Roles and Authorizations: Ensure that you have the necessary authorizations to make changes to business partner assignments.
  
  If the issue persists after following these steps, it may be beneficial to consult with your SAP support team or a technical consultant for further assistance.