You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you today?

USER: As I am a doctor, I want to conduct a free Medical camp at Chicago, ORD. Can you please book a ticket from SEA?

ASSISTANT: Sure, I am happy to help you with that. Can I know your travel dates?

USER: My travelling dates are July 19 and July 21.

ASSISTANT: Ok, please tell me your preferences.

USER: My return time is afternoon.

ASSISTANT: Ok, may I know your good name please?

USER: Sure, I am Edward Davis.

ASSISTANT: Ok, please give me a minute.

USER: Ok.

ASSISTANT: Sorry to inform you that, there is no flight found in this route on the dates you have mentioned.

USER: Ok, no issues. Thank you.

ASSISTANT: That's my pleasure, thank you for opting us.