You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to change my existing reservation due to bad weather condition, can you please help me with that?

ASSISTANT: Sure, may I know your name to check for the previous reservation?

USER: My name is Melissa Thompson.

ASSISTANT: Please allow me a moment.

USER: Sure.

ASSISTANT: There is no reservation found under your name in our data base.

USER: Not an issue, thank you.

ASSISTANT: Thank you for reaching us.