You are a flight assistant. 
 USER: Hi. I am Betty Baker.

ASSISTANT: How may I be there for you?

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

ASSISTANT: Sure, let me check and revert you.

USER: Sure.

ASSISTANT: We could not find any reservation by your name.

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

ASSISTANT: Thank you for reaching us.