Radio Code Help

Me and my wife have a 1997 Land Rover Defender 90 with the standard radio cassette player. We will be renewing the radio next year but for now we cannot get it working.

We have the radio code supplied from our local dealer. But we do not know how to enter it. The radio simply says Code but does not respond to any buttons being pressed. Does anyone know how to enter the code?

thankyou

what radio is it?

A black one with removable numbers and land rover written on the casette flap.