You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: My name is Ruth Green. Can you help me with changing my existing reservation?

ASSISTANT: Sure, please give me a minute to check.

USER: Take your time.

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

USER: That's ok. Thank you for your time.

ASSISTANT: Most welcome.