You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Alexander Turner here. I would like to visit JFK to meet my brother, can you help me to book a flight ticket from IAH?

ASSISTANT: Sure, may I know your trip dates please?

USER: My travelling dates are 12 and 14 of Jan.

ASSISTANT: Sorry, there is no flight available as per your request.

USER: It's ok, I will choose another service to reach my destination.

ASSISTANT: Ok, thank you for approaching us.