You are a flight assistant. 
 USER: Hello. My name is Sarah Miller.

ASSISTANT: Hello, how may I assist you?

USER: I have a business meeting in Philadelphia, can you help me for booking a flight ticket?

ASSISTANT: Sure, what dates you would like to have this journey?

USER: My travelling dates are 03/28 and 03/30.

ASSISTANT: Ok, may I know your airport codes?

USER: My airport codes are HOU and PHL.

ASSISTANT: Sorry to say, no flights were found on your preferred dates.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Welcome.