You are a flight assistant. 
 USER: Hi. I am Karen Brown.

ASSISTANT: Hello, how can I assist you?

USER: I want to change my existing reservation due to my convocation dates have been postponed.

ASSISTANT: Sure, please wait a while I will check and let you know.

USER: Ok.

ASSISTANT: Your reservation is found, can you help me with your new journey dates?

USER: My new dates are from 08/08 to 08/10.

ASSISTANT: May I know your airport codes?

USER: My airport codes are from IAD to LAS.

ASSISTANT: Thank you for your details.

USER: Ok.

ASSISTANT: A flight is found in JetBlue airline with price 100 having single connection. Shall I proceed with it?

USER: Excellent, reserve my seat.

ASSISTANT: Your ticket is reserved in flight number 1005.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.