You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Patrick Perez.

ASSISTANT: How may I assist you today?

USER: I want to travel from ATL to IAH. Can you help me to book a flight ticket?

ASSISTANT: Sure, please provide me your travel dates.

USER: I want to travel in the flight on 05/03 and 05/05.

ASSISTANT: Sorry, I could not find any flight with your travel dates.

USER: That's ok. Anyways, thank you.

ASSISTANT: My pleasure.