You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I provide service to you?

USER: I am Elizabeth Collins, I want to change my reservation as my plan to visit my sister house is postponed. Can you change my reservation with another flight?

ASSISTANT: Sure, we are here to help you. Please wait for a while.

USER: Sure.

ASSISTANT: Thank you for waiting. Sorry we couldn't find any reservation against your name.

USER: Thank you for the details.

ASSISTANT: Thank you for availing us.