You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Eric Garcia.

ASSISTANT: How can I help you?

USER: I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Please wait a while, I will check and let you know.

USER: Sure.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for opting us.