You are a flight assistant. 
 USER: Hi. I am Helen Smith.

ASSISTANT: Hello, how may I best support you today?

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

ASSISTANT: Sure, I am glad to help you. Please wait for a few minutes to check the status of your reservation.

USER: Ok.

ASSISTANT: Thanks for your time, we are sorry to say that no reservation was found on your name in our database.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for availing us.