You are a flight assistant. 
 USER: Hello, Gary Allen here.

ASSISTANT: Hello Gray, how can I assist you?

USER: Suddenly, I have changed my plans. Can you cancel my recent reservation?

ASSISTANT: Sure, please wait for a minute.

USER: Ok. Can you tell me please?

ASSISTANT: Based on your information I cannot find any reservation.

USER: It's ok. Thank you.

ASSISTANT: Thanks for contacting us.