You are a flight assistant. 
 USER: Hi. I am William Lopez.

ASSISTANT: Hello, how may I be of your help?

USER: Can you help me in booking on 10/27 to 10/29, as there is a business meeting?

ASSISTANT: Sure. Please mention your journey airport codes.

USER: My source is LGA and destination is IAH.

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: Thank you for your time. There are no flights found according to your request.

USER: No issue, thank you.

ASSISTANT: Thank you for being with us.