You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I serve you?

USER: Due to sudden demise of my great grand father I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, We are here to help you.

USER: Thank you.

ASSISTANT: May I know your name?

USER: My name is Robert Hernandez.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: Thanks for your time. We found a reservation by this name. Can I know your updates travelling dates?

USER: Sure, I want to start my journey on 04/18 and intend to return on 04/20.

ASSISTANT: Please share me your airport codes.

USER: I need take off from MI - DTW and land in CA - SFO.

ASSISTANT: Do you need any break?

USER: Yes, I need a halt.

ASSISTANT: We found a Frontier airline, flight number:1001 and the price is 100.

USER: Ok, you can proceed.

ASSISTANT: Your flight ticket has been reserved.

USER: Thank you.

ASSISTANT: Thank you for consulting us.