You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, do you need any help from us?

USER: Can you please change my recent reservation details? As my planned trip has been postponed.

ASSISTANT: Ok, could I have your name please?

USER: Sure, my name is Jessica Brown.

ASSISTANT: Ok, please allow me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation with your name in our portal to make changes further.

USER: Oh! That's ok, thank you for giving the information anyways.

ASSISTANT: You are welcome, have a great day.