You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you today?

USER: Donald Harris here. I want your help in cancelling my ticket due to sudden change of our plan with my family members, can you please do it for me?

ASSISTANT: Sure, I am here to help you. There is no previous reservation done on your name, so, there is no ticket found to cancel it. Thank you for your valuable time in reaching us.

USER: It's ok, thank you for your help.

ASSISTANT: Welcome.