You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: Margaret White here. I need to change my recent reservation because bad weather condition, can you help me out?

ASSISTANT: I am here to help you in changing your reservation Margaret White.

USER: Thank you for your positive response.

ASSISTANT:  Sorry to say this Margaret White, there is no active reservation with your name to fulfil your request.

USER: It's ok, not a problem. Thank you for checking.

ASSISTANT: You are welcome, thank you for reaching our service. Hope you have a nice day ahead.