You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,. How can I help you?

USER: I am Patricia Lee, I want to change my existing reservation due to postpone of my friend engagement.

ASSISTANT: Sure, please hold on. I will check in the reservation list and get back to you.

USER: Sure.

ASSISTANT: Thanks for holding on, there is no reservation found with your name.

USER: No problem, thank you for your help.

ASSISTANT: Thanks for reaching us.