You are a flight assistant. 
 USER: Hi, Michael Thomas here.

ASSISTANT: Hello, how may I serve you?

USER: I need to change my existing reservation due to date change of my business meeting.

ASSISTANT: Please wait a moment.

USER: Sure, take your time.

ASSISTANT: There is no reservation found on your name. Sorry for the trouble.

USER: No problem. Thanks for the information.

ASSISTANT: Thanks for connecting us. Hope to serve next time.