You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Jeffrey Johnson.

ASSISTANT: How can I aid you?

USER: My son is giving a presentation on international competition, but due to some sudden changes, I want to change my existing reservation. Could you help me in changing my reservation?

ASSISTANT: Sure, I can here to help you out. Please wait for a minute.

USER: Ok.

ASSISTANT: Thanks for being waiting. We didn't found any reservation by this name.

USER: Ok, no issues. Thanks for your help.

ASSISTANT: Thank you for consulting us.