You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I would like to change my flight reservation as my trip got postponed, can you please help me?

ASSISTANT: Ok, I am here to help you with that. Can I know your name?

USER: My name is William Jackson.

ASSISTANT: Sorry William Jackson, there is no active reservation under your name.

USER: No issue, thank you for your time.

ASSISTANT: You are welcome, thank you for reaching us.