You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me with changing my previous reservation for my health checkup?

ASSISTANT: Sure, may I know your name please?

USER: My name is Dorothy Brown.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there was no reservation found with your given name.

USER: Oh! That's fine. Thank you for checking.

ASSISTANT: Thank you for opting us.

USER: You are welcome.