You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Andrew Carter, want to travel from HOU to DFW. Please help me in booking my ticket.

ASSISTANT: Sure, may I know your trip dates?

USER: My trip dates are from 06/01 to 06/03.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: It's ok, thank you.

ASSISTANT: You are welcome.