You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I amend you today?

USER: I made a reservation earlier to meet my family doctor but, on that date due to emergency operation I cannot meet doctor. So. I want to change my reservation, can you help me in this?

ASSISTANT: Sure, may I know your good name in changing your reservation?

USER: Charles Gonzalez is my name.

ASSISTANT: Thank you for providing your name.

USER: OK.

ASSISTANT: I regret that there is no reservation found on your name.

USER: Ok, no problem in that.

ASSISTANT: Thank you for making us to support you.

USER: Thanks for the information.