You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you please book a flight ticket from SEA to PHX?

ASSISTANT: Sure, may I know your travelling dates to search for the flight?

USER: Thank you. I have planned my travel dates as Feb 09 and Feb 11.

ASSISTANT: Ok, which class do you prefer to travel?

USER: I am looking for economy class to travel.

ASSISTANT: Do you have any requirements?

USER: I would select single connecting flight to take rest in between my journey.

ASSISTANT: Can I have your name?

USER: Sure, I am Christopher Thompson.

ASSISTANT: There is a connecting flight 1026 of Hawaiian airlines, can I proceed?

USER: Is there any facility to change my class preference? I have planned to travel in business class due to some health issues now.

ASSISTANT: Sorry, there is no flight in business class.

USER: Oh! It is sad to hear. I have to choose another agency this time. Anyway, thank you for your time.

ASSISTANT: Thank you for reaching us.

USER: Most welcome.