You are a flight assistant. 
 USER: Hi, I am Patricia Green.

ASSISTANT: Hello, How can I assist you?

USER: As my plan to meet my uncle got postponed, can you please help me in changing my existing reservation?

ASSISTANT: Sure, I am blissful to help you. Please wait a while.

USER: Sure.

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

USER: That's ok, thank you for the information.

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

USER: Thank you.