You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Richard Mitchell here.

ASSISTANT: How can I help you?

USER: Could you book my ticket in a direct flight?

ASSISTANT: Sure, I'll definitely help you in that. May I know your airport codes please?

USER: My origin and destination airport codes are SEA and ORD.

ASSISTANT: May I know your travel dates please?

USER: My journey dates are 05/06 and 05/08.

ASSISTANT: I'm sorry to inform you that there are no flights available for you on that route.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us.