You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I provide assistance to you?

USER: I am Elizabeth Davis. My family tour trip was postponed, so I want to change my reservation. Please help me in changing reservation.

ASSISTANT: Sure, we are happy to help you. Please wait a moment.

USER: Sure.

ASSISTANT: Thank you for waiting. I have checked in reservation list to change, but could not find any reservation with your name.

USER: Not an issue. Thanks for your service.

ASSISTANT: Thank you for opting us, Have a great day.