You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I address you?

USER: Can you please help me to change me existing reservation as I have changed my trip plan?

ASSISTANT: Sure, will you please let me know your name to check the status and revert you?

USER: My name is Jeffrey King.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting Jeffrey King, I have gone through the reservation list but could not find any reservation by your name.

USER: No problem, thank you for your time in checking it.

ASSISTANT: Thank you for opting us.