You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: I want to change my existing reservation, can you help me in changing my reservation?

ASSISTANT: Sure, We are here to help you. May I know your name?

USER: Thank you, my name is Kathleen Lopez.

ASSISTANT: Give me a minute.

USER: OK.

ASSISTANT: Thanks for your time. We didn't found any reservation by this name.

USER: Ok. No problem, leave it. Thanks for the information.

ASSISTANT: Thanks for your reaching us.