You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Jerry Wilson. I am planning to change my reservation to another destination, so can you help me to change my reservation?

ASSISTANT: Sure, I will help you with that.

USER: Ok.

ASSISTANT: Please wait while I look for your existing reservation.

USER: Ok.

ASSISTANT: I tried my best but couldn't find your reservation.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you.