Good morning @Luiz_Carlos_de_Azeve,
I am looking for just a bit more information to help find a solution to this.
Within the Getting Started with the ESP8266 and DHT22 Sensor blog post, there is a note before the code:
You’ll need to increase the underlying MQTT library’s memory limit. The PubSubClinet MQTT library has a default memory limit that is not enough to support all the values that the DHT22 sensor can collect. The error is also not apparent, which makes it hard to track. To increase the memory limit, please check out this forum post.
If you have not completed this step, errors can arise. If you have completed this step, and are still getting the error, let me know and we will try again!
Thanks,
Julia