Worldpay saysIntegration issue
451Advice message already received
What it means
Duplicate transaction
An identical payment was sent very recently, so this one was blocked.
What to do
Confirm whether the first one succeeded before sending again, and use unique order references.
Don't retry as-isWho can fix it: You, the merchant
Yuno response codeDUPLICATED_TRANSACTION
Reference only. Codes and descriptions come from each provider's public documentation. The Yuno response code is a reference mapping and does not guarantee how a specific transaction is processed.