diff --git a/app.js b/app.js
index b3c3c2a..1a3530b 100644
--- a/app.js
+++ b/app.js
@@ -99,6 +99,17 @@ const mediaCodecs = [
   },
 ]
 
+const closeCall = (callId) => {
+  if (videoCalls[callId]) {
+    videoCalls[callId].producer?.close();
+    videoCalls[callId].consumer?.close();
+    videoCalls[callId]?.consumerTransport.close();
+    videoCalls[callId]?.producerTransport.close();
+    videoCalls[callId].router.close();
+    delete videoCalls[callId].router;
+  }
+}
+
 const getRtpCapabilities = (callId, callback) => {
   console.log('[getRtpCapabilities] callId', callId);
   const rtpCapabilities = videoCalls[callId].router.rtpCapabilities;
@@ -118,14 +129,18 @@ peers.on('connection', async socket => {
   })
 
   socket.on('createRoom', async ({ callId }, callback) => {
-    console.log(`[createRoom] socket.id ${socket.id} callId ${callId}`);
-    if (!videoCalls[callId]) {
-      console.log('[createRoom] callId', callId);
-      videoCalls[callId] = { router: await worker.createRouter({ mediaCodecs }) }
-      console.log(`[createRoom] Router ID: ${videoCalls[callId].router.id}`)
+    if (callId) {
+      console.log(`[createRoom] socket.id ${socket.id} callId ${callId}`);
+      if (!videoCalls[callId]) {
+        console.log('[createRoom] callId', callId);
+        videoCalls[callId] = { router: await worker.createRouter({ mediaCodecs }) }
+        console.log(`[createRoom] Router ID: ${videoCalls[callId].router.id}`);
+      }
+      socketDetails[socket.id] = callId;
+      getRtpCapabilities(callId, callback);
+    } else {
+      console.log(`[createRoom] missing callId ${callId}`);
     }
-    socketDetails[socket.id] = callId;
-    getRtpCapabilities(callId, callback);
   })
 
   // Client emits a request to create server side Transport
@@ -159,14 +174,9 @@ peers.on('connection', async socket => {
     console.log(`[transport-produce] Producer ID: ${videoCalls[callId].producer.id} | kind: ${videoCalls[callId].producer.kind}`)
 
     videoCalls[callId].producer.on('transportclose', () => {
+      const callId = socketDetails[socket.id];
       console.log('transport for this producer closed', callId)
-      
-      // https://mediasoup.org/documentation/v3/mediasoup/api/#producer-close
-      videoCalls[callId].producer.close()
-
-      // https://mediasoup.org/documentation/v3/mediasoup/api/#router-close
-      videoCalls[callId].router.close()
-      delete videoCalls[callId]
+      closeCall(callId);
     })
   })
 
@@ -200,7 +210,6 @@ peers.on('connection', async socket => {
           console.log('transport close from consumer', callId)
           
           // https://mediasoup.org/documentation/v3/mediasoup/api/#router-close
-          stvideoCallsate[callId].router.close()
           videoCalls[callId].producer.close()
           videoCalls[callId].consumer.close()
           delete videoCalls[callId].router
@@ -211,10 +220,7 @@ peers.on('connection', async socket => {
           console.log('producer of consumer closed', callId)
           
           // https://mediasoup.org/documentation/v3/mediasoup/api/#router-close
-          videoCalls[callId].router.close()
-          videoCalls[callId].producer.close()
-          videoCalls[callId].consumer.close()
-          delete videoCalls[callId].router
+          closeCall()
         })
 
         // from the consumer extract the following params