diff --git a/proxy/main.go b/proxy/main.go
index b0f6971..399493b 100644
--- a/proxy/main.go
+++ b/proxy/main.go
@@ -19,7 +19,7 @@ func main() {
 	unsafeLogging := flag.Bool("unsafe-logging", false, "prevent logs from being scrubbed")
 	keepLocalAddresses := flag.Bool("keep-local-addresses", false, "keep local LAN address ICE candidates")
 	relayURL := flag.String("relay", sf.DefaultRelayURL, "websocket relay URL")
-	NATTypeMeasurementIntervalString := flag.String("nat-retest-seconds", "24h",
+	NATTypeMeasurementIntervalString := flag.String("nat-retest-interval", "24h",
 		"the time interval in second before NAT type is retested, 0s disables retest. Valid time units are \"s\", \"m\", \"h\". ")
 
 	flag.Parse()