You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Margaret Walker.

ASSISTANT: How can I help you Walker?

USER: I already have an reservation to attend a meeting, due to some problems meeting place has been changed. So I need a few changes in my reservation. Can you please help me?

ASSISTANT: Sure, I will help you. Please give me a minute.

USER: Ok, take your time.

ASSISTANT: Sorry Walker, I did not find any active reservation by your name.

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

ASSISTANT: It's my pleasure, have a nice day.