You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: I am Deborah Carter, want to book my round trip ticket from Washington, DC - IAD. Can you please help me in ticket booking?

ASSISTANT: Sure, I will help you with that. Can you please mention your travelling dates?

USER: My travelling dates are from Jan 26th to Jan 28th.

ASSISTANT: Do you need any halt in between your journey?

USER: No, I don't want any halt.

ASSISTANT: Do you prefer any other class?

USER: No.

ASSISTANT: Ok, please wait for a while. Sorry, no flight found on your given database.

USER: It's ok, thank you.

ASSISTANT: Thank you for reaching us.