You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you today?

USER: Can you help me in changing my reservation, as my plan to go for a vacation got postponed.

ASSISTANT: Let me know your name.

USER: I am Cynthia Walker.

ASSISTANT: Sure, Please wait for a while.

USER: Ok.

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

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you.