COMMUNITY

I'm looking at https://support.snatchbot.me/v1.0/reference and trying to get this to work.
I can send an initial 'get' request and for a first-time user I see see no messages. Fine.
I can send a post request with a message and user ID as per the reference doc and I get the first screen back. If however I post anything else on behalf of that user id, I get nothing returned until the session has timed out at your end.

# => {"cards"=>[], "messages"=>["How can I help?"], "speech"=>"", "status"=>true, "suggested"=>nil}

but send anything else within a few minutes and....

# => nil 

Is there a problem or am I doing something completely wrong?