You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Gary Roberts.

ASSISTANT: How can I assist you?

USER: I want to change my reservation because the information is not correct in the recent reservation. Can to aid me?

ASSISTANT: Sure, I will help you to change your reservation.

USER: Ok.

ASSISTANT: Sorry Roberts, there is no reservation found on your name to change your reservation.

USER: That's fine, no issue. Thank you for your help.

ASSISTANT: Welcome.