You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: William Green here.

ASSISTANT: How can I help you now?

USER: Because of my health issues, I just want to cancel my recent reservation, so can you help me for this?

ASSISTANT: That's sad to hear, I will help you with that.Please wait for a while.

USER: Ok, I will wait for your response.

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

USER: Oh! It's ok, no problem. Thank you for your quick response.

ASSISTANT: Thank you for approaching us, have a nice day.