Trying to set up Google Speech Kit Plugin

Hi there, I just bought this plugin from the marketplace Google Speech Kit in Code Plugins - UE Marketplace and I’m following the documentation to set it up. (GitHub - IlgarLunin/UE4GoogleSpeechKit-docs: Documentation page for GoogleSpeechKit ue4 plugin).

My blueprint is all set up as documentation say (see image below) but when it arrives to “Google STT” node nothing happen.

I don’t even know if my API key is working.

Any help?
thank in advance

Here is my blueprint setup:

It should be the same of the documentation (except for the “play sound” left there).

Is there anything I’m missing in calling API key or in Google TTS?