Illuminate\Support\Facades\Facade::clearResolvedInstance PHP Method

    public static function clearResolvedInstance($name)
    {
        unset(static::$resolvedInstance[$name]);
    }

 /**
  * Send the given request through the middleware / router.
  *
  * @param  \Illuminate\Http\Request  $request
  * @return \Illuminate\Http\Response
  */
 protected function sendRequestThroughRouter($request)
 {
     $this->app->instance('request', $request);
     Facade::clearResolvedInstance('request');
     $this->bootstrap();
     return (new Pipeline($this->app))->send($request)->through($this->middleware)->then($this->dispatchToRouter());
 }