Oauth2 issue with passport-zendesk : Failed to fetch user profile

✖  ERROR     RuntimeError: Failed to fetch user profile 
err[name] InternalOAuthError
err[message] Failed to fetch user profile
err[oauthError] {
  statusCode: 401,
  data: '{"error":"invalid_token","error_description":"The access token provided is expired, revoked, malformed or invalid for other reasons."}'
}
----------------------------------------------------------------------
  oauth2.get('https://' + subdomain + '.zendesk.com/api/v2/users/me.json', accessToken, function(err, body) {
    var json;
    var profile = {};

    if (err) {
      return done(new InternalOAuthError('Failed to fetch user profile', err));
    }