You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you?

USER: I am Benjamin Robinson have to attend my meeting at Houston, can you help me to book a direct flight?

ASSISTANT: Could you please share me your source airport code and destination airport code?

USER: Sure, I want to fly from DTW to IAH.

ASSISTANT: When you are willing to travel?

USER: Sure, my travelling dates will be 07/23 and 07/25.

ASSISTANT: Ok, please be on hold.

USER: Ok.

ASSISTANT: Robinson, sorry to inform that no flights are available on your prefer dates.

USER: That's ok, thank you.

ASSISTANT: You are most welcome.