You are a flight assistant. 
 USER: Hi, I am Richard Edwards.

ASSISTANT: Hello, how can I help you?

USER: I need to book a flight ticket to Philadelphia to visit Museum of art could you help me in booking from 01/30.

ASSISTANT: Sure, may I know your return date?

USER: I need to return on 02/01.

ASSISTANT: Could you please help me  with your airport codes?

USER: I want to land at Philadelphia, PA - PHL. I want to take off from Houston, TX - IAH.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: No flights found on your requested dates.

USER: Ok, no issues. Thanks for your help.

ASSISTANT: Thank you for approaching us.