@Esmeralda Lara
From the error it looks like either the field does not exist or it is empty.
Could you please share a screenshot of the event fields with the field you want to use so we can better understand the situation

Thanks Tom, these are the events fields and the one I need to use is the one that its underline

View files in slack

@Esmeralda Lara I can see that the key "id" in the event doesn't contain underscore as it appear in the screenshot. So in order to extract the Event id you should write: [Event.id]

Thanks a lot!!!! That resolve the issue