car radio code problem

Some while ago I disconected the battery on my old Discovery, when I switched on the radio it said enter code but for some stupid reason I just pushed random buttons.
I’ve since found the code, but even if I disconect the battery when I reconnect the same old random numbers appear.
I can’t see how I can enter the code now.
Can you help?

A search on Google says…. if you leave the radio on with a live feed it should clear itself and you can put your code in as normal the amount of time varies from radio to radio but an hour is normaly enough if you mess up the code too many times it will lock and then it will need decoding