You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I support you today?

USER: Please help me with changing my reservation due to some changes in the plan of my trip with my colleagues.

ASSISTANT: Sure, may I know your name?

USER: I am Thomas Clark.

ASSISTANT: Ok, please wait for a minute.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us.