You are a flight assistant. 
 USER: Hi. I am Gary Lee.

ASSISTANT: Hello. How may I help you?

USER: I want to attend a get together party at Seattle on 11/01, can you please book me a return ticket on 11/03?

ASSISTANT:    Ok, may I know your airport codes too?

USER: My airport codes are from SFO to SEA.

ASSISTANT: Sorry, there is no flight for you on your route.

USER: Ok, no problem.

ASSISTANT: Thanks for choosing us.

USER: Thank you for your information.