You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Rachel Davis.

ASSISTANT: How may I guide you today?

USER: I am planning to meet my uncle at Washington on 04/29 and I intend to return on 05/01, so can you help me with booking?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Can you please share your source and destination airport codes?

USER: Yes, my airport codes are WA-SEA and DC-DCA.

ASSISTANT: Please wait for a minute.

USER: Ok.

ASSISTANT: I am sorry to say that there is no flight found under your name.

USER: That's ok. Thank you for the response.

ASSISTANT: Thank you for your reaching us, have a great day.