You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Sandra Mitchell. I already have an reservation to attend a  meeting, due to some problems meeting place has been changed.

ASSISTANT: Ok.

USER: So I need a few changes in my reservation. Will you do it?

ASSISTANT: Sure, I will modify your reservation as on your request.

USER: Thank you.

ASSISTANT: Give me a minute, let me check the reservation list.

USER: Take your time.

ASSISTANT: Sorry, we could not find your reservation in our database.

USER: Not a issue.

ASSISTANT: Hope we serve you next time.

USER: Thank you for your kind information.