You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I want to flight ticket with the price of 500, can you please book me a ticket?

ASSISTANT: Sure, may I know your good name?

USER: My name is Kevin Martinez.

ASSISTANT: Could you please provide your journey dates?

USER: My journey dates are from 03/20 to 03/22.

ASSISTANT: Please provide your journey airport codes.

USER: My airport codes are from SEA to SFO.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: We are very sorry to notify you that there is no flights found based in your journey dates.

USER: Ok, no issues.

ASSISTANT: Thanks for choosing us.

USER: Thanks for your response.

ASSISTANT: Have a nice day.