Hello Noémi Gönczi,
Keep in mind this is not a supported portion of Tableau, but a third party sample.
So unfortunately, these things can happen. It's possible that there is a bug in the connector, or maybe even Facebook made a small change to their API.
I invite you to try again to see if it works now.
In the meantime, have you tried this?
It might do the trick as well: Tableau Now Loves Cloud Data | Cognetik Cloud Connector
There is a discussion here with the devs if you want to: Facebook Sample Connector Thread
Lénaïc RIÉDINGER, Global Community Engineer Tableau
If you see a Helpful or Correct response, please mark it thanks to the buttons below the targeted post!
I have had success connecting with the Cognetik Cloud Connector but repeatedly hit a low maximum of exports. For example, no more that 50 posts can be exported at a time. Any suggestions?