code: protected function renewAccessToken()
      {
          $token = $this->authorizer->getApi()
              ->getAuthorizerToken(
                  $this->authorizer->getAppId(),
                  $this->authorizer->getRefreshToken()
              );
  
          $this->authorizer->setAccessToken($token['authorizer_access_token'], $token['expires_in'] - 1500);
  
          return $token['authorizer_access_token'];
      }
docs: Refresh authorizer access token.
  
  @return string