3187150 - Why is the Withholding Tax not updated on Payable to Supplier in the Invoice Reconciliation?

I created an invoice with no taxes. The external tax engine calculated the sales tax and the SAP Ariba native tax engine calculated the Withholding tax (WHT) at the invoice reconciliation (IR) line item level. Why is the WHT not updated on the Payable to Supplier when it is present in the line item?

SAP Ariba Buying & Invoicing

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