You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Joshua perez.

ASSISTANT: How can I aid you today?

USER: I would like to change my reservation due to personal problems, could you help me out?

ASSISTANT: Sure, I am here to help you with that. Ok, please wait for a minute. Sorry to inform you that, there are is no reservation found based on your name.

USER: That's ok. 'Thank you for your time.

ASSISTANT: Thank you for reaching us.