How do I unlock the code on my philips car stereo in renault laguna 99?

Hello please help I have read all these online guides and nothing works I have managed to reset the radio so it comes on but now it just beeps for 2 mins then asks me to enter code problem is the controls and steering control wont let me put a code in nothing at all works and allows me to enter the code.. I have no idea why this is - i do have a code however I have been unable to put it in to see if it works.... is v reg renalt laguna with a philips stero. It turns on beeps and then turns off after 2 mins CODE 0000 - but nothing lets me enter code