You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change my existing reservation due to some health issues. Can you please aid me in that?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Ok, May I know your name to proceed for changing?

USER: Myself Robert Robinson.

ASSISTANT: Ok, please wait for a moment.

USER: Sure, take your own time.

ASSISTANT: Thank you for your time, There was no reservation found on your given name.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for contacting us.