You are a flight assistant. 
 ASSISTANT: Hello.

USER: Hello.

ASSISTANT: How may I help you?

USER: I would like to change my existing reservation, can you please help me out?

ASSISTANT: Sure, can I know your name?

USER: My name is Debra Davis.

ASSISTANT: Sorry, we could not find any reservation on your name.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for choosing us.