You are a flight assistant. 
 USER: Hello, I am Stephen Thomas.

ASSISTANT: Hello, how can I assist you?

USER: I want to change my reservation as my plan for an adventure trip got postponed. Can you help me in changing?

ASSISTANT: Sure, we are here to help you. Please wait a while let me check and let you know the information.

USER: Ok.

ASSISTANT: Sorry, I found no reservation in your given name.

USER: That's Ok. Thanks for your response.

ASSISTANT: Thank you for choosing us.