You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today?

USER: Due to some issues, I am willing to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, may I know your name?

USER: Please check under the name Mark Scott.

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

USER: No issue, thank you for checking.

ASSISTANT: Thank you for choosing us.