You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: Could you please help me to book a direct flight form Boston to treat an emergency case in Houston?

ASSISTANT: Sure, may I know your travelling dates?

USER: Sure, I need to depart on 03/05 and my return date will be on 03/07.

ASSISTANT: Can I know your airport codes?

USER: My boarding and landing airport codes are BOS and IAH.

ASSISTANT: May I know your other specifications?

USER: No more specifications.

ASSISTANT: May I know your name?

USER: I am Cynthia Carter.

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

USER: That's ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for choosing us.