You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Patricia Roberts.

ASSISTANT: Yes, Roberts.

USER: My trip dates have been postponed, can you help me in changing my reservation?

ASSISTANT: Sure, please let me check your reservation status.

USER: Sure.

ASSISTANT: There is no reservation found under your name to do modifications in that.

USER: That's fine. Anyway, thank you for your help.

ASSISTANT: Thank you for choosing us.