P2P-09

Control Description

SAP automatically checks for duplicate vendor invoices during PO invoice entry. If a new invoice matches key details of a previously posted bill (such as the vendor, invoice date, reference number, company code, and amount), the system triggers an error message that blocks the duplicate posting.

Risk

The company could accidentally process and pay the same PO invoice twice due to duplicate submissions or processing errors, resulting in unauthorized financial outflows.

Implementation Details

When an invoice is entered, the system compares specific fields of the current document against historical invoices already posted in the system

## How It Is Implemented
Step 1 Configure Tolerances and Control Parameters in Customizing (OMR6 / SPRO)
• Go to SPRO (IMG path): Materials Management > Logistics Invoice Verification > Incoming Invoice > Check Duplicate Invoice
• Here, you can configure whether the system should check based on the reference number (XBLNR) alone or a combination of fields,

Step 2: Set the Duplicate Check Flag in the Vendor Master
• The duplicate check relies on the vendor master record, managed via transaction BP (Business Partner) in S/4HANA under the Vendor: Company Code financial role.
• Go to the Payment Transactions tab. and set the "Check double invoice" indicator

Test Procedures

A- Test of Design (TOD)

• Inspect SPRO (IMG path): Materials Management > Logistics Invoice Verification > Incoming Invoice > Check Duplicate Invoice
• Verify that the duplicate invoice check is enabled and configured correctly for the relevant company codes.

A- Test of Operating Effectiveness (TOE)

• Review a sample of vendor master records in transaction BP to verify that the "Check double invoice" indicator is active by default in the template/creation process for active vendors.

• Negative Testing (Attempting to Post a Duplicate):
◘Select a previously posted, valid invoice in the system (e.g., from MIRO history). Attempt to create a new invoice in MIRO using the exact same matching parameters (same Vendor, Company Code, Amount, Currency, and Reference Number / Invoice Number).
◘Expected Result: The system issues a warning message (M8 108) and/or applies an automatic payment block, preventing accidental disbursement.