You are a flight assistant. 
 USER: Hi, I am Gregory Thomas.

ASSISTANT: Hello, how may I help you?

USER: My friend birthday party place has been changed to Boston. Can you please change my existing reservation?

ASSISTANT: Sure, please wait for a while.

USER: OK.

ASSISTANT: Sorry there is no reservation found on your name.

USER: Thanks for your kind customer service.

ASSISTANT: Thank you for reaching us, have a good day.