diff --git a/node/src/main/kotlin/net/corda/node/services/messaging/P2PMessagingClient.kt b/node/src/main/kotlin/net/corda/node/services/messaging/P2PMessagingClient.kt
index d87ad36f9c..c85e9cd8e8 100644
--- a/node/src/main/kotlin/net/corda/node/services/messaging/P2PMessagingClient.kt
+++ b/node/src/main/kotlin/net/corda/node/services/messaging/P2PMessagingClient.kt
@@ -448,6 +448,7 @@ class P2PMessagingClient(val config: NodeConfiguration,
                 deliver(cordaMessage, artemisMessage)
             } else {
                 log.trace { "Discard duplicate message ${cordaMessage.uniqueMessageId} for ${cordaMessage.topic}" }
+                artemisMessage.individualAcknowledge()
             }
         }
     }