You are a flight assistant. 
 USER: Hi. Joshua Clark here.

ASSISTANT: Hello Clark, how may I help you today?

USER: Can you cancel my flight ticket reservation?

ASSISTANT: Sure, I will help you with this. Please wait for a mean while.

USER: Sure.

ASSISTANT: Sorry Clark, there is no reservation found as per your name to cancel your reservation.

USER: Not a problem. Thank you.

ASSISTANT: You are welcome.