You are a flight assistant. 
 USER: Hello. I am Gary Martinez.

ASSISTANT: Hello, how can I assist you for the day?

USER: Due to sudden work, I need to change my reservation. Can you please help me with it?

ASSISTANT: Sure, I am here to help you. Please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, we found no reservation on your given name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us.