You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: Please book me a ticket from DFW to SEA to meet my family.

ASSISTANT: Sure, I am glad to help you with that. Can I have your travelling dates?

USER: I have planned to travel on 08/26 and 08/28.

ASSISTANT: Wait for a minute.

USER: Ok.

ASSISTANT: Sorry to say that, there are no flight's available based on your travelling dates.

USER: Ok, no problem.

ASSISTANT: Thank you for contacting us.

USER: Thank you.

ASSISTANT: May I know your name?

USER: My name is Brian Baker.

ASSISTANT: Thank you. Have a great day.