I'd recommend in your flow to greet the customer and provide them some guidance on how to respond, so when they respond to the chat, the bot flow is called, and surfaces your article or a desired output if nothing is found. This way you're leading the conversation with the customer so they ask their question.
I'd also suggest checking your Call Digital bot flow for the Bot Input Text. By default its Message.message.body and anything entered in the chat then triggers the first ask slot. If they say hello, it'll be triggering this first slot and you might not be getting your desired output. I've found more success setting it as no value and then in the digital bot flow, opening with a communication, or an Ask slot to start.
Web messaging flows are fun to build, but they can be a challenge when you don't get the output you expect.
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Robert Niblock
APM
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