You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, How may I assist you?

USER: I want to book a flight ticket to attend the Jazz event in Seattle.

ASSISTANT: Ok, please provide travel dates and airport codes to book you a ticket.

USER: My source is IAD and destination is SEA. I will start on 07/20 and return on 07/22.

ASSISTANT: May I know your name? to process further.

USER: I am Benjamin Martin.

ASSISTANT: Ok, thanks for sharing your details. Wait a minute.

USER: Ok.

ASSISTANT: We checked it, but no flights on your travel days.

USER: Ok, not a problem.

ASSISTANT: Thanks for choosing us.

USER: Thanks for your response.