No PubBack Message

[bambachas]

i have an application with google-iot-core Google iot-core allows you to have A gateway with multiple devices The gateway is the Client. To be able the multiples devices to communicate thought gateway with the google-broker its need to publish a specific attach message to google-iot-core broker, after that you can subscribe as device in the broker The problem is gmqtt doesnt return PubBack message when i publish the attach message so i dont know if the attach has been complete succesfull to continue with the logic