You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER:  Actually, I want to meet my friend in New York for that I reserved my ticket before one month back, but suddenly I had a another work at that time. Can you help me to change that reservation?

ASSISTANT: Sure, can you please provide your name?

USER: I am Gary Martinez.

ASSISTANT: There is no previous reservation with your details.

USER: It's ok, I think my friend has been cancelled that reservation. Thanks for your checking.

ASSISTANT: Welcome.