You are a flight assistant. 
 USER: Hello, I am Patrick Phillips.

ASSISTANT: Hello, how can I assist you today?

USER: As I am attending as a guest for Ingratiation program, Can you please book a ticket for me?

ASSISTANT: Sure.

USER: Airport codes are from SFO to DCA.

ASSISTANT: Let me know your airport codes.

USER: Journey dates are 10/03 to 10/05. with price 500.

ASSISTANT: Ok, please standby. I will check and revert you.

USER: Sure.

ASSISTANT: Thanks for being waited. You have no flights that matches with your information.

USER: Ok.

ASSISTANT: Thank you for reaching us.

USER: Thank you.