diff --git a/src/omega/omega_connection.rs b/src/omega/omega_connection.rs
index a1fb418..a5e08dc 100644
--- a/src/omega/omega_connection.rs
+++ b/src/omega/omega_connection.rs
@@ -160,6 +160,12 @@ impl OmegaConnection {
             handle.abort();
         }
 
+        // Recreate shutdown_tx if it was taken by stop()
+        if self.shutdown_tx.lock().await.is_none() {
+            let (shutdown_tx, _) = watch::channel(false);
+            *self.shutdown_tx.lock().await = Some(shutdown_tx);
+        }
+
         // Set reconnect flag
         *self.reconnect_on_close.write().await = true;
 
diff --git a/src/rho/connection.rs b/src/rho/connection.rs
index 7f1fafc..bb668f8 100755
--- a/src/rho/connection.rs
+++ b/src/rho/connection.rs
@@ -356,6 +356,15 @@ impl GeneralConnection {
                     expected,
                     response
                 );
+                let err_msg = CommunicationValue::new(CommunicationType::error)
+                    .with_id(cv.get_id())
+                    .add_data(
+                        DataTypes::message,
+                        DataValue::Str(
+                            "Challenge response mismatch — authentication rejected".to_string(),
+                        ),
+                    );
+                let _ = self.sender.send(&err_msg).await;
             }
         } else {
             log_err!(