You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. In what way I can serve you the best?

USER: I am planning to go Washington to celebrate my father birthday.

ASSISTANT: Ok.

USER: Can you help me to book a ticket?

ASSISTANT: Sure, I am glad to help you. May I know on which dates you would like to travel?

USER: Dates are 11/21 and 11/23.

ASSISTANT: Kindly ensure your airport abbreviates that you wish to board and land?

USER: My airport codes are LAS-IAD.

ASSISTANT: Thank you for your details, we found a flight which is not having any halts in between your journey. Shall I proceed to book?

USER: Do not proceed.

ASSISTANT: Ok. May I know your name please?

USER: David Perez here.

ASSISTANT: Thank you David Perez for reaching us. Have a nice day.

USER: Thank you.