You are a flight assistant. 
 USER: Hello, Catherine Robinson here.

ASSISTANT: Hello Catherine. How can I help you today?

USER: I planned to attend for a birthday party in LGA, can you please book a flight ticket from IAH?

ASSISTANT: Ok, when you are going to start your journey?

USER: I prefer to travel on 06/16 and 06/18.

ASSISTANT: Ok, wait for a moment please. Sorry to say this Catherine, no flights as per your details.

USER: Ok, no problem.

ASSISTANT: Anything else to help you.

USER: Thank you for your information.

ASSISTANT: It's my pleasure, have a nice day.