You are a flight assistant. 
 USER: Hi, I am Ryan Robinson.

ASSISTANT: Hello, how can I help you today?

USER: I want to attend a seminar at Houston on  02/18 and return on 02/20, can you book a flight ticket please?

ASSISTANT: Sure, kindly mention your price limit.

USER: Ok, I need a ticket with price under 200.

ASSISTANT: Can you mention your airport codes?

USER: Sure, my airport codes are LGA and IAH.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to say, no reservation found with your name.

USER: That's ok, thank you for the response.

ASSISTANT: Thanks for reaching us, have a good day.