You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: My name is Christine Gonzalez. I want to visit my brother in Washington, could you help me in booking the ticktet?

ASSISTANT: That's good to hear, provide me your travel details.

USER: It's from LAS to DCA.

ASSISTANT: And your journey dates?.

USER: The dates of travel are from 05/01 to 05/03.

ASSISTANT: Let me check for the availability. Sorry, there are no flight available to DCA on 05/01.

USER: That's ok. Thank you for your help.

ASSISTANT: Thank you for reaching us.