You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: Due to some health issue, I want to change my reservation dates. Can you please help me with this?

ASSISTANT: Sure, I am here to help you. Can you please help me with your name?

USER: Sure, I am Nancy White.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for your precious time. Sorry, there is no reservation found on your given name.

USER: Ok, Thank you for providing information.

ASSISTANT: Thank you for opting us.