You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I have planned to consult a doctor for monthly check up at Los Angeles, CA - LAX. Will you help me in booking a flight ticket?

ASSISTANT: Ok. May I know your travelling dates please?

USER: Sure, my travelling dates are 07/28 and 07/30.

ASSISTANT: Where will you start your journey?

USER: I would like to start my journey from Denver, CO - DEN.

ASSISTANT: Do you have any other specifications?

USER: I need a single connection.

ASSISTANT: Let me know your good name please?

USER: My name is Donna Campbell.

ASSISTANT: Thanks for sharing your details, no connecting flights are available with your request.

USER: Ok, no problem. Thank you.

ASSISTANT: Thanks for availing us.