You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Mark Williams.

ASSISTANT: How may I guide you?

USER: I want to cancel my recent reservation, due to some health issue. Can you please help me out?

ASSISTANT: Mark Williams, I am here to help you for this. Let me check your reservation status in our records?

USER: Sure, I will wait for your information.

ASSISTANT: Sorry to intimate you, no reservation is found with your criteria.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you very much for approaching our agency.