You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I want to change my existing reservation, so can you help me in changing my reservation?

ASSISTANT: Sure, can I know your name please?

USER: My name is Steven Perez.

ASSISTANT: Ok, wait a moment please.

USER: Sure, take your time.

ASSISTANT: Sorry Perez, there is no reservation found on your name.

USER: That's ok, I will check for other alternatives.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your information.