You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I want to change my reservation with new vacation, can you help me to change reservation?

ASSISTANT: Sure, I can help you, meanwhile may I know your name for searching your previous booking?

USER: Gregory King here.

ASSISTANT: King, I did not came across your name in the reservation list to change it. Is there any other help that you need from my side?

USER: It's ok, not a issues. No, thanks. Thanks for checking.

ASSISTANT: Ok, thank you for reaching us and using our service. Have a great day.