You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am Christine Brown, want to alter my recent reservation due to sudden changes in my trip. Please help me out with that.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name to change.

USER: It's ok, thank you for your help.

ASSISTANT: Most welcome.