https://userapps.support.sap.com/sap/support/knowledge/en/2078846
2078846 - How to Correct the Posting Date of an Open Payment in Supplier Account | SAP Knowledge...
You have an open payment in the supplier account with the posting date as e.g., 01.11.2014 but the actual posting date is suppose to be as 07.11.2014 and you...