You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Patricia Carter here.

ASSISTANT: How may I assist you Carter?

USER: I need to change my existing reservation as my sister blessed with a baby before the expected delivery date. Please help me with that.

ASSISTANT: Sure. Patricia Carter, actually there is no reservation found on your name.

USER: Fine, thank you for the information.

ASSISTANT: Thank you for choosing us.