Heroku H18 error with Microsoft OAuth 2.0

Question

I am trying to build a simple OAuth 2.0 authentication flow for Microsoft/outlook ID. I have tested the flow on localhost everything seems to be working in that.

But when I deploy the APP to Heroku with new Microsoft app credentials and RedirectURI of the Heroku app. It gives H18 error when redirecting to the logincomplete page.

I am able to get the code in the URL, ID_token, and the refresh token.

Relevent information:

• Development environment: Nodejs

• libraries: simple-oauth2,express,express-session.

Heroku logs

sock=backend at=error code=H18 desc="Server Request Interrupted" method=GET path="/auth/outlook/callback?code=###-###-###-###-###" host=####.herokuapp.com request_id=... fwd="##.##.##.##" dyno=web.1 connect=1ms service=646ms status=503 bytes= protocol=https

Code for redirectUri

app.get('/auth/outlook/callback', async (req, res) => {
            const code = req.query.code;
            const options = {
              code,
              redirect_uri: redirectUri,
              scope : scopes.join(' ')
            };

        try {
            const result = await oauth2.authorizationCode.getToken(options);

            console.log('The resulting token: ', result);

            var token = oauth2.accessToken.create({ refresh_token: result.refresh_token, expires_in: 0});



              email = authHelper.getEmailFromIdToken(result.id_token);

              User.findOne({emailId:email})
                .then((existingUser) => {
                  if(existingUser){
                    //We already have a new user
                  }else {
                    new User({emailId : email}).save();
                  }
                });

              req.session.access_token = token;
              req.session.refresh_token = token.refresh_token;
              req.session.email = email;

              console.log(token);

        // Check if the token is expired. If expired it is refreshed.

                if (token.expired()) {
                  try {
                    token =  token.refresh();
                  } catch (error) {
                    console.log('Error refreshing access token: ', error.message);
                  }
                }

              return res.status(200).json().redirect('/logincomplete');

            } catch(error) {
              console.error('Access Token Error', error.message);
              return res.status(500).json('Authentication failed');
            }
          });

Values of token, email and other variables are set correctly by this code.

Please give suggestions on how to solve this issue.

Also, If you can suggest some passport-strategy package to work with this stuff instead of simple-oauth2. I have tried passport-outlook and passport-Microsoft.

Thanks in Advance.