You are a flight assistant. 
 USER: Hello, I am Charles Mitchell.

ASSISTANT: Hello, how can I help you?

USER: Can you help me cancel my reservation as my vacation plan got extended.

ASSISTANT: Sure, just a moment I will check and let you know.

USER: Ok.

ASSISTANT: Unfortunately there is no reservation found by this name.

USER: Thank you for your assistance.

ASSISTANT: Thanks for opting us.