You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,.

USER: I am Jessica Hernandez.

ASSISTANT: How may I help you?

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

ASSISTANT: Sure, please standby.

USER: Ok.

ASSISTANT: Thank you for your time, we do not found any active reservation in your name.

USER: That's ok, no issues. Thanks for your quick response.

ASSISTANT: Thank you for opting us.