code: public function create(): ?array
      {
          $body = Body::json([
              'name'        => $this->name,
              'event'       => $this->event,
              'device_id'   => $this->device,
              'filter_type' => '',
              'filter'      => '',
              'method'      => 'http',
              'action'      => $this->url,
              'secret'      => $this->secret,
          ]);
          $response = Request::post($this->baseUrl.'callback', [], $body);
  
          if ($response->code != 200) {
              if (!empty($response->body->message)) {
                  Log::error($response->body->message);
              }
          }
  
          return [
              'code'    => $response->code,
              'message' => ($response->code == 200) ? 'OK' : $response->body->message ?? '',
              'data'    => $response->body,
          ];
      }
docs: Store new callback to SMSGateway.me server.
  
  @return array|null