You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Karen Nelson. I am planning to visit a NASA space center in Houston, so please book a flight ticket from Denver.

ASSISTANT: Sure, can I know your preferable dates?

USER: I will start on 08/13, return on 08/15.

ASSISTANT: Ok, let me know your source and destination airport codes?

USER: My source and destination airport codes are CO - DEN, TX - HOU.

ASSISTANT: We found a flight from Hawaiian airline with 1 connection and fare is 100. Shall I proceed?

USER: You can proceed to booking.

ASSISTANT: Your ticket is booked and flight number is 1013.

USER: Thank you for your good service.

ASSISTANT: Thank you for reaching us.