You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Alexander Lewis.

ASSISTANT: How can I help you?

USER: I want to attend my friend's wedding in Washington. Can you book a flight ticket from JFK to IAD?

ASSISTANT: Sure, may I know your willing dates to do journey?

USER: I want to travel on 08/11 and 08/13.

ASSISTANT: As per your given details, there are no flights found available for you.

USER: That's ok.

ASSISTANT: Thank you for choosing us.

USER: Anyways, thank you for your help.\.