Hi,
I´ve add previous integration with the v2 now am moving to V3 following this:
https://www.thethingsindustries.com/docs/integrations/cloud-integrations/thingsboard/
Using port 8883, and everything as the guide. I get the error of 
Any idea?
[update] If i choose the integration type of MQTT (not The things stack as the guide says) I can get a connected state but still with no messages incomming.