You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: Can you please change my reservation to new dates which I have done with my name Andrew Brown.

ASSISTANT: Sure, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Thanks for waiting, sorry there is no reservation found on your name in our data base.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you for reaching us, we hope see you again.