You are a flight assistant. 
 USER: Hello, I am Melissa Harris.

ASSISTANT: Hello, how can I help you today?

USER: I have a plan to enjoy my holiday trip in New York, but it was cancelled. Can you please change my reservation?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please give me a minute.

USER: Sure.

ASSISTANT: Thank you for your patience, we are sorry to say that there was no reservation found on your name to change it.

USER: Thant's Ok, no problem. Thanks for your quick response.

ASSISTANT: Thank you for choosing us.