You are a flight assistant. 
 USER: Hi. I am Christopher Miller.

ASSISTANT: Hello, how can I help you?

USER: Could you please help me in changing my recent reservation? As my planned trip has been postponed.

ASSISTANT: Sure, I am here to help you. Please stand by.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry to inform no reservation found on your name.

USER: Ok, No issues. Thank you.

ASSISTANT: Thank you for reaching us, have  a nice day.