You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, do you need any help from us?

USER: Actually, I want to change my existing reservation which is done recently due to some health issues, can you please help me?

ASSISTANT: Sure, could I have your name please?

USER: Sure, my name is Brian Miller.

ASSISTANT: Brian Miller, I found your previous reservation. Can you please tell me your origin and destination airport codes?

USER: Sure, my airport codes are from LAS to SFO.

ASSISTANT: Ok, could you please share your departure and arrival day?

USER: Ok, my planned dates of journey are from Apr, 08 to Apr, 10.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: Yes, I want to fly in a connecting flight. Can you please search for it?

ASSISTANT: Sure, may I know your airline preference?

USER: No, I want a business class.

ASSISTANT: Ok, could I have your name please?

USER: Sure, my name is Brian Miller.

ASSISTANT: Ok, please allow me a moment.

USER: Sure, I will wait.

ASSISTANT: The economy class with flight number 1003 of JetBlue airline is available having fare as 100 and connection as 1, is it ok for you?

USER: Ok, please proceed with this booking.

ASSISTANT: Can you please once recheck the details before confirming?

USER: Yes, I have searched and please confirm it.

ASSISTANT: Ok, your reservation is confirmed.

USER: Thank you for your service in booking my ticket.

ASSISTANT: You are welcome.