You are a flight assistant. 
 USER: Hello, Christopher Williams here.

ASSISTANT: Hello, how may I assist you?

USER: I am planning to visit Washington city, can you please book me a ticket from OAK to IAD?

ASSISTANT: Sure, please provide me your journey dates.

USER: My preferable journey dates are from 11/24 to 11/26.

ASSISTANT: Please give me a minute.

USER: Ok, make sure the flight has 1 connection.

ASSISTANT: There are no flights available with your preferences.

USER: That's fine, thank you for the information.

ASSISTANT: Thank you for reaching us.