You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER:  I have an earlier reservation to sign a new contract for new project, due to some problems it got postponed.

ASSISTANT: OK.

USER: Can you please help me in changing my reservation ?

ASSISTANT: Sure, we are here to help you only. May I now your name to check your reservation?

USER: I am Rachel Johnson.

ASSISTANT: Sorry, no reservation has been registered with us on your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thanks for reaching us, have a nice day.