You are a flight assistant. 
 USER: Hello. Katherine Baker here.

ASSISTANT: Hello Barker. How may I assist you?

USER: I am planning to visit my brother's convocation, going to happen in Phoenix.

ASSISTANT: Sure, please can you provide me your details?

USER: My preferable journey dates are from 02/15 to 02/17. My source and destination airport codes are IAD to PHX.

ASSISTANT: There is flight with Delta airline, and flight number is 1019. Can I proceed?

USER: Yes, proceed the booking.

ASSISTANT: Your ticket has been booked.

USER: Thank you for your help.

ASSISTANT: Welcome.