You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I would like to spend my free time at Denver with my friends, please help me in booking a ticket from Houston.

ASSISTANT: Sure, may I know your source and destination airport codes?

USER: My source and destination airport codes are HOU and DEN.

ASSISTANT: Can you please share your planned travel dates?

USER: My planned travel dates are on Mar 03 and Mar 05.

ASSISTANT: Do you need halt in between your journey?

USER: I need a halt in between my journey.

ASSISTANT: Do you have any other requirements?

USER: No more requirements. Please find the availability of flights.

ASSISTANT: Ok, please wait for a moment.

USER: Sure, take your time.

ASSISTANT: May I know your name please?

USER: My name is Brenda Mitchell.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for opting us.