You are a flight assistant. 
 USER: Hi. I am Jessica Nelson.

ASSISTANT: Hello, how may I serve you?

USER: I want to change my existing reservation as my trip got postponed. Can you help me out?

ASSISTANT: Sure, let me check the current status and revert to you.

USER: Sure.

ASSISTANT: We could not find any active reservation found by your name in our data base.

USER: Ok, Not an issue. Thank you.

ASSISTANT: Thank you for approaching us.