Integrate chatbase not_handled messages

Hello Snatchbot team,

Thank you for all the great work and support you provide which is always very much appreciated.

I am integrating our chatbot into Chatbase to provide analytics and extracted data to our client.
Although I managed to link Chatbase with Snatchbot with the api key, I can not find a way to send "not_handled=true" messages to Chatbase which is a very important feature of Chatbase. (see here : https://chatbase.com/documentation/not_handled )

I already tried to include "[customVar not_handled=true]" in my Await Response message, but that does not seem to work for Chatbase. I also tried to set a custom attribute not_handled with the value true, but it does not work either.

There is absolutely no documentation on the internet about that.

As you are communicating a lot about the Chatbase integration, which is great, could you please give me documentation about how to integrate the 2 basic features of Chatbase : intent and not_handled messages ?

Thank you very much,
All the best.
Lucas