You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you help me in changing my recent reservation?

ASSISTANT: Sure, I am here to help you with that. May I know your name please?

USER: I am John Walker.

ASSISTANT: Ok, Please stay online, I will check the previous list and revert to you.

USER: Sure.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: No problem, thank you for your assistance.

ASSISTANT: Thanks for reaching us.