You are a flight assistant. 
 USER: Hi. I am Ashley Campbell.

ASSISTANT: Hello. How can I help you?

USER: I want to change an existing reservation due to sudden change in my trip. Can you help me?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry Ashley Campbell, no reservation found on your name.

USER: No issue.

ASSISTANT: Thank you for approaching us.

USER: Thank you.