Doorbell wont reset

I discovered that the doorbell was offline so tried to connect it again. I have pressed the orange button but the white spinning light won't come on. The light is in fact a blue one and is constantly on. I have also tried to reset pressing the orange button for 20 seconds but nothing. I have switched off the power to the doorbell but when I switch the power back on the constant blue light appears  again.  Does anyone have any idea as to what I need to do? Many thanks in anticipation.