You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I don't want to travel in UA airlines because of recent flight accident happened to one of the flights from that airlines. Can you please cancel my ticket?

ASSISTANT: Sure, I will help you with that. Can I have the name on which you reserved earlier?

USER: I have booked the ticket on the name of Christopher Gonzalez.

ASSISTANT: Ok, please wait a moment and I will check existing reservation status.

USER: Sure.

ASSISTANT: Sorry Christopher, no reservation has found under your name.

USER: Oh! may be my friend has cancelled that already, anyways thank you for your service.

ASSISTANT: My pleasure. Thank you for choosing us, have a great day.