You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I am Jacob Roberts. I want to change my reservation due to health problem, can you help me?

ASSISTANT: Sure, I will help you to cancel your reservation.

USER: Thank you.

ASSISTANT: Please wait I will check for the previous reservation and take an action according to it.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name to change your reservation.

USER: No problem, thanks for checking.

ASSISTANT: Welcome, have a nice day.