You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Ronald Jackson here.

ASSISTANT: How can I assist you, Jackson?

USER: Co-incidentally, I gave wrong dates for my previous reservation. So, can you alter my previous reservation?

ASSISTANT: Sure, give me a minute.

USER: Sure.

ASSISTANT: Sorry Jackson, there is no reservation found on your name.

USER: It's fine. Anyway, thank you.

ASSISTANT: You are welcome.