You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Betty Lewis here.

ASSISTANT: What help is required from my end Betty?

USER: I would like to visit Washington DC to organize an event so please help me booking of flight on dates of 02/27 and 02/29.

ASSISTANT: Sure, could you please provide the take off and landing airport codes?

USER: Sure, I would like to travel from LAS to IAD.

ASSISTANT: Give me a moment please, I will revert back to you.

USER: Sure, take your time.

ASSISTANT: UA airline is providing a service in your route with price 200, can I proceed?

USER: That's fine, please go for booking.

ASSISTANT: Your reservation has been done with flight number 1015.

USER: Thank you for helping me.

ASSISTANT: You are welcome, visit us again.