You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Brian Lewis.

ASSISTANT: How may I aid you today?

USER: I want to book a ticket from LGA to HOU to meet my grandparents, can you please help me in booking?

ASSISTANT: Sure, I am oblige to help you. Can you please provide your preferable travelling dates?

USER: I am departing on 11/18 and return on 11/20.

ASSISTANT: Ok, please wait a moment to check the flights availability.

USER: Sure.

ASSISTANT: Sorry, there are no flights found in your route with your requested dates of travelling.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for reaching us, have a great day.