You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Jonathan Hernandez here. Please book a ticket from DFW to SEA.

ASSISTANT: Sure Jonathan, can I know the travel dates please?

USER: My trip dates are from 08/26 and 08/28.

ASSISTANT: Ok, wait a moment please.

USER: Sure.

ASSISTANT: Sorry, there are no flight on your dates.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you for choosing us.