You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I  help you?

USER: I am Matthew Mitchell. I would like to book a ticket from SFO to PHL, can you help me?

ASSISTANT: Ok, may I know your trip dates?

USER: My travel dates are 10/17 and 10/19.

ASSISTANT: Hold on a moment.

USER: Sure.

ASSISTANT: Sorry, there is no flight found on your route to book your ticket.

USER: No problem, thanks for checking.

ASSISTANT: Thanks for choosing us.