You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Brian Gonzalez. Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: Sorry Brian Gonzalez, there is no active reservation found under your name in our records.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Most welcome.