You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: Could you please book me a flight ticket from IAH to ATL?

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: I am planning to start on July 20th and return on July 22nd.

ASSISTANT: Are you looking for a connecting flight or direct flight?

USER: I need a connecting flight only.

ASSISTANT: Do you have any other requirements that you are looking for?

USER: I am looking for an economy class.

ASSISTANT: Can you please provide your name to proceed further?

USER: I am Lisa Young.

ASSISTANT: Sorry, there are no flights available at your request.

USER: That's alright, thanks for your assistance.

ASSISTANT: Thank you for contacting us, have a nice day.