You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Anthony Moore.

ASSISTANT: How may I help you for the day?

USER: I want to change my existing reservation due to my friend's marriage were postponed.

ASSISTANT: OK. Please wait for a moment, As we have to search for your reservation details.

USER: Ok, take your time.

ASSISTANT: We are very sorry to inform you that, There is no reservation found on Anthony Moore.

USER: Not a problem. Thank you for your help.

ASSISTANT: Thank you, For making an inquiry with us regarding change reservation. Have a great day.