You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I want to change my existing reservation, because I have another important work on that dates. so can you please help me in changing my reservation?

ASSISTANT: Sure, let me check for your reservation status.

USER: Ok.

ASSISTANT: For checking, may I know your name please?

USER: Sure, my name is Helen Phillips.

ASSISTANT: Phillips, I have found a reservation by your name. May I know your travel dates?

USER: I want to departure on 08/29 and please book my return ticket also on 08/31.

ASSISTANT: Ok, can you please provide me your airport codes?

USER: I want to take off from DEN airport and destination airport is MSP.

ASSISTANT: Flight-1004 of JetBlue airlines is available with 1 connection, shall I book your ticket?

USER: Please book this flight ticket on my name.

ASSISTANT: Sure, your ticket is booked successfully.

USER: Thank you for assisting me.

ASSISTANT: Thank you for contacting us.

USER: Welcome.