diff --git a/JavaScript/client.js b/JavaScript/client.js
index 8644fa8..6630242 100644
--- a/JavaScript/client.js
+++ b/JavaScript/client.js
@@ -27,7 +27,11 @@ class Client {
 
   static async getInstance(req, res) {
     const client = new Client(req, res);
-    await Session.restore(client);
+    try {
+      await Session.restore(client);
+    } catch {
+      throw new Error("Couldn't restore session");
+    }
     return client;
   }
 
diff --git a/JavaScript/server.js b/JavaScript/server.js
index daa7125..bc8f4cc 100644
--- a/JavaScript/server.js
+++ b/JavaScript/server.js
@@ -5,6 +5,8 @@ const http = require('node:http');
 const Client = require('./client.js');
 const Session = require('./session.js');
 
+const INVALID_TOKEN_CODE = 498;
+
 const routing = {
   '/': async () => '<h1>welcome to homepage</h1><hr>',
   '/start': async (client) => {
@@ -46,7 +48,13 @@ const types = {
 };
 
 http.createServer(async (req, res) => {
-  const client = await Client.getInstance(req, res);
+  try {
+    const client = await Client.getInstance(req, res);
+  } catch {
+    res.statusCode = INVALID_TOKEN_CODE;
+    res.end();
+    return;
+  }
   const { method, url, headers } = req;
   console.log(`${method} ${url} ${headers.cookie}`);
   const handler = routing[url];
diff --git a/JavaScript/session.js b/JavaScript/session.js
index ea66627..d845d28 100644
--- a/JavaScript/session.js
+++ b/JavaScript/session.js
@@ -43,7 +43,10 @@ class Session extends Map {
     if (sessionToken) {
       return new Promise((resolve, reject) => {
         storage.get(sessionToken, (err, session) => {
-          if (err) reject(new Error('No session'));
+          if (err) {
+            reject(new Error('No session'));
+            return;
+          }
           Object.setPrototypeOf(session, Session.prototype);
           client.token = sessionToken;
           client.session = session;