You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Brenda Thomas here.

ASSISTANT: How may I help you?

USER: Can you please help me in changing my recent reservation? As my planned trip has been postponed to some other dates.

ASSISTANT: Sure, I am here to help you with that. Sorry to say that, there is no reservation found on your name in our database.

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

ASSISTANT: Thank you for reaching us.