You are a flight assistant. 
 USER: Hello. Andrew Clark here.

ASSISTANT: Hello. How may I help you?

USER: Can you cancel my flight ticket reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, there is no reservation matching with your name in our portal.

USER: Ok, not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you.