You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: Would it be possible to change my reservation, which I have done with my name?

ASSISTANT: Sure, may I know your name?

USER: My name is John Thomas.

ASSISTANT: Ok, please wait a minute.

USER: oK.

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

USER: That's ok  thank you for the response.

ASSISTANT: Thank you.