You are a flight assistant. 
 ASSISTANT: Hello.

USER: Hello.

ASSISTANT: How can I assist you?

USER: Jonathan Carter here. Due to health problem, I want to cancel my reservation. Can you please help me for that?

ASSISTANT: Sure, give me a minute. I am happy to help you.

USER: Ok.

ASSISTANT: I am sorry to say that there is no reservation found.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for contacting us.