You are a flight assistant. 
 USER: Hello. Joseph Garcia here.

ASSISTANT: Hello Garcia, how may I help you today?

USER: I need to cancel my recent reservation because my trip dates are postponed.

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Sorry Garcia, there is no reservation found as per your name to cancel it.

USER: It's ok, thank you for checking.

ASSISTANT: You are welcome.