How To Fix EK356 - Entry found in the correspondence container is not unique

SAP Error Message - Details

• Message type: E = Error

• Message class: EK - IS-U Accounts Receivable and Payable

• Message number: 356

• Message text: Entry found in the correspondence container is not unique

What causes this issue?

The following entries in the correspondence container are ambiguous:
Business partner: &V1&
Contract account: &V2&
Returns document: &V3&

System Response

A returns notification cannot be printed.

How to fix this error?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message EK356 - Entry found in the correspondence container is not unique ?

  The SAP error message EK356, which states "Entry found in the correspondence container is not unique," typically occurs in the context of document processing, particularly when dealing with purchasing documents or invoices. This error indicates that there are multiple entries in the correspondence container that match the criteria being processed, leading to ambiguity.
  Causes:
  
  Duplicate Entries: There may be multiple entries in the correspondence container for the same document or criteria, which SAP cannot resolve.
  Configuration Issues: The configuration settings for the correspondence container may not be set up correctly, leading to multiple entries being created for the same document.
  Data Integrity Issues: There may be issues with the data integrity in the database, such as incorrect or duplicate records.
  Custom Development: If there are custom developments or enhancements in the system, they may inadvertently create duplicate entries.
  
  Solutions:
  
  Check for Duplicates: Review the entries in the correspondence container to identify any duplicates. You can do this by using transaction codes like SE16 or SE11 to view the relevant database tables.
  Adjust Configuration: If the issue is related to configuration, review the settings for the correspondence container in the relevant customizing transactions (e.g., SPRO) and ensure that they are set up correctly.
  Data Cleanup: If duplicates are found, you may need to clean up the data by removing or consolidating duplicate entries. This should be done carefully to avoid data loss.
  Review Custom Code: If there are custom developments, review the code to ensure that it is not causing the creation of duplicate entries. You may need to involve a developer to assist with this.
  Consult SAP Notes: Check the SAP Support Portal for any relevant SAP Notes that may address this specific error message or provide guidance on resolving it.
  Contact SAP Support: If the issue persists and you cannot identify the cause, consider reaching out to SAP Support for assistance.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with transaction codes like ME23N (Display Purchase Order), ME2N (Purchase Orders by PO Number), and others that may help you investigate the issue.
  Database Tables: Understand the relevant database tables involved in the correspondence container, such as EKKO (Purchasing Document Header) and EKPO (Purchasing Document Item).
  Documentation: Review SAP documentation related to purchasing and invoice processing for additional context on how the correspondence container is used.
  
  By following these steps, you should be able to identify the cause of the EK356 error and implement a solution to resolve it.