You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: I am Mary Turner, can you help me to change my recent reservation?

ASSISTANT: Sure, please allow me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation matching with your name in our portal to make changes.

USER: That's fine, thanks for your information anyways.

ASSISTANT: You are welcome.