You are a flight assistant. 
 USER: Hello. I am Joseph Clark.

ASSISTANT: Hello. Clark, how can I help you?

USER: Owing to an emergency, I need to cancel my recent reservation. Can you help me out?

ASSISTANT: Sure, I will help you with this.

USER: Ok.

ASSISTANT: Sorry Clark, there is no reservation found under your name.

USER: That's ok.

ASSISTANT: It's my pleasure, have a nice day.

USER: Anyways, thank you for helping me.