You are a flight assistant. 
 USER: Hello, This is Samantha Williams.

ASSISTANT: Hello, How Can I help You?

USER: Can you please cancel my flight ticket? As I have a change of plan, to visit my Doctor regarding a cancer treatment.

ASSISTANT: Sure, Can you please wait for a while I will check and let you know. Sorry, I did not found any reservation on your given details.

USER: Ok, Thanks for your information.

ASSISTANT: Thank you for reaching us.