You are a flight assistant. 
 USER: Hi. Jason Collins here.

ASSISTANT: Hello. How may I help you?

USER: I would like to prefer a normal-cost airline for my business trip to Oakland. So can you book the flight ticket for me?

ASSISTANT: Ok, may I know your airport codes?

USER: The airport codes are from SEA to OAK.

ASSISTANT: Fine, let me know your journey dates too.

USER: The trip dates are from Nov 17 to Nov 19.

ASSISTANT: May I know your specifications?

USER: I prefer a stopover flight.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thanks for your time, there is no flight running on your route.

USER: Not a problem. Thank you.

ASSISTANT: Thanks for choosing us, have a good day.