diff --git a/pkg/rtc/types/interfaces.go b/pkg/rtc/types/interfaces.go
index 53bbc6676..a90b481ad 100644
--- a/pkg/rtc/types/interfaces.go
+++ b/pkg/rtc/types/interfaces.go
@@ -149,6 +149,8 @@ func (p ParticipantCloseReason) ToDisconnectReason() livekit.DisconnectReason {
 		return livekit.DisconnectReason_SERVER_SHUTDOWN
 	case ParticipantCloseReasonSimulateServerLeave:
 		return livekit.DisconnectReason_SERVER_SHUTDOWN
+	case ParticipantCloseReasonNegotiateFailed:
+		return livekit.DisconnectReason_STATE_MISMATCH
 	default:
 		// the other types will map to unknown reason
 		return livekit.DisconnectReason_UNKNOWN_REASON