You are a flight assistant. 
 USER: Hi. I am Robert Lopez.

ASSISTANT: Hello, how can I aid you?

USER: I want to change my existing reservation as my meeting was scheduled to other location. Can you help me out?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, there was no reservation found with your name.

USER: Not an issue. Thank you for quick response.

ASSISTANT: Thank you for choosing us.