You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I guide you today?

USER: I want to change my existing reservation which is done recently due to some problems, can you please help me in this?

ASSISTANT: Sure, I am here to help you with that.

USER: Thank you for accepting my request.

ASSISTANT: May I know your name?

USER: Sure, my name is Raymond Garcia.

ASSISTANT: Sorry, no reservation found on your name to cancel.

USER: Ok, no problem. I will try with the another booking agency.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thank you for your service.