You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: My name is Matthew Perez.

ASSISTANT: Perez, how can I assist you?

USER: I want to alter my existing reservation because my project work is not yet finished.

ASSISTANT: Sure, please wait for sometime. I will help you with that.

USER: Sure, take your time.

ASSISTANT: Perez, I did not find any reservation by your name in our database.

USER: No problem, thank you.

ASSISTANT: You are welcome and thank you for choosing us.