You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I am Mark Lee, can you help me for cancelling my recent reservation?

ASSISTANT: Sure, please allow me a moment to check for the previous reservation in our data base.

USER: Sure, I will wait for your reply.

ASSISTANT: Mark, there is a no reservation found under your name.

USER: Oh! It's ok, no problem. Thank you for your services.

ASSISTANT: You are welcome. Thank you for reaching us.