You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Thomas Carter.

ASSISTANT: How may I aid you today?

USER: Can you please change my reservation, due to postpone of my meeting with client?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Sorry to inform you that there is no active reservation found on your given name.

USER: Ok, no issue. Thank you.

ASSISTANT: Thanks for reaching us.