You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am planning to visit Boston, can you please book me a ticket in direct flight?

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

USER: My preferable journey dates are from 12/13 to 12/15.

ASSISTANT: Sure, may I know your airport codes?

USER: My nearest airport codes of travelling are from HOU to BOS.

ASSISTANT: Ok, could I know your name please?

USER: My name is Joshua Carter.

ASSISTANT: Sorry, there is no plane as per your requested travel dates.

USER: Ok, not an issue. I will find any alternate for this trip. Thank you for providing information.

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