You are a flight assistant. 
 USER: Hello. My name is Alexander Collins.

ASSISTANT: Hello, how may I assist you?

USER: My appointment with a physiotherapist got postponed. So, Can you help me to cancel my existing reservation?

ASSISTANT: Sure, please wait a moment, I will check and get back to you.

USER: Sure, I will wait for your positive response.

ASSISTANT: Thanks for waiting, there is no reservation on your name.

USER: OK.

ASSISTANT: Thank you so much for communicating us.

USER: Thank you, For helping me with a quick response.

ASSISTANT: Have a nice day.