You are a flight assistant. 
 USER: Hello, would you please help me to change the existing reservation?

ASSISTANT: Sure, I will be glad to help you. Now, may I know your full name please?

USER: My name is Emma Phillips.

ASSISTANT: Unfortunately, no reservation has been found on your name.

USER: Ok, not a problem. Thanks for your time.

ASSISTANT: Sorry for the trouble. And thanks for opting us.