diff --git a/labs/bbb-webrtc-sfu/lib/base/BaseManager.js b/labs/bbb-webrtc-sfu/lib/base/BaseManager.js
index 9e7320b2a0736339c506a30bce60bab4d321fe68..8a88e671fc1cc671d87eaa75a8399a0f8d405ecc 100644
--- a/labs/bbb-webrtc-sfu/lib/base/BaseManager.js
+++ b/labs/bbb-webrtc-sfu/lib/base/BaseManager.js
@@ -137,7 +137,7 @@ module.exports = class BaseManager {
   }
 
   _handleError (logPrefix, connectionId, streamId, role, error) {
-    if (this._validateErrorMessage(error)) {
+    if (error && this._validateErrorMessage(error)) {
       return error;
     }
 
diff --git a/labs/bbb-webrtc-sfu/lib/screenshare/ScreenshareManager.js b/labs/bbb-webrtc-sfu/lib/screenshare/ScreenshareManager.js
index 2353a1fec88d780269e0bc11d5a47f3c098a2760..0b42746094435f241c632105be9d90ed77f91274 100644
--- a/labs/bbb-webrtc-sfu/lib/screenshare/ScreenshareManager.js
+++ b/labs/bbb-webrtc-sfu/lib/screenshare/ScreenshareManager.js
@@ -135,7 +135,7 @@ module.exports = class ScreenshareManager extends BaseManager {
       }
       if (role === C.RECV_ROLE && session) {
         Logger.info(this._logPrefix, "Stopping viewer " + sessionId);
-        await session.stopViewer(message.connectionId);
+        await session.stopViewer(connectionId);
       }
     }
   }