You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I want to change an existing reservation as my meeting got postpone due to technical issues, can you please help me?

ASSISTANT: Sure, may I know your name please?

USER: I made a reservation by this name Samantha Campbell.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry Samantha Campbell, there is no active reservation found with your name in our records.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Most welcome.