You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: Can you help me to change my reservation?

ASSISTANT: Sure, may I know your name?

USER: I am George Green.

ASSISTANT: Ok, please wait for some time.

USER: Sure.

ASSISTANT: Thanks for waiting, there is a reservation found on your name. Please share your travelling dates?

USER: My travel dates are Oct 06 and Oct 08.

ASSISTANT: May I know your airport codes?

USER: My airport codes are DTW and LGA.

ASSISTANT: Do you have any specifications?

USER: I would like to prefer business class flight ticket.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.