You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I want to change my existing reservation due to postpone of my document verification in my college. Can you help me in doing that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: May I know your name please to check the status of your reservatin?

USER: Sure, I am Debra Perez.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Thanks for waiting, no active reservation found on your name to change it.

USER: Ok, no issues.

ASSISTANT: Thank you for choosing us.

USER: Thank you.