You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, may I know your name?

USER: Ronald Parker is here.

ASSISTANT: How can I assist you?

USER: I just want to change my reservation due to my friends were changed the tour dates.

ASSISTANT: Sure, Wait a minute.

USER: Ok.

ASSISTANT: I regret to inform you that there is no reservation found with your name.

USER: Not an issue.

ASSISTANT: Thanks for choosing us.

USER: Thank you for quick response.