How To Fix 1P161 - Payment item with external reference number &1 is already updated

1P161 - Overview

• Message type: E = Error

• Message class: 1P - BCA: Payment Transactions

• Message number: 161

• Message text: Payment item with external reference number &1 is already updated

What causes this issue?

It emerged that a payment item already exists with the specified
reference number from payment transactions.

System Response

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

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.

1P161 - Details

• The SAP error message 1P161 indicates that a payment item with a specific external reference number has already been processed or updated in the system. This typically occurs in the context of financial transactions, such as payment processing or reconciliation, where duplicate entries are not allowed.
  
  Cause:
  
  
  Duplicate Processing: The most common cause of this error is that the payment item has already been processed or updated in the system. This can happen if:
  
  The same payment was submitted multiple times.
  There was a system error that caused the payment to be recorded more than once.
  Manual entry errors where the same external reference number is used for different transactions.
  
  
  
  Data Integrity Issues: There may be issues with data integrity, where the system does not recognize that the payment has already been processed due to inconsistencies in the database.
  
  
  Timing Issues: If multiple users or processes are trying to update the same payment item simultaneously, it can