Barons VW Tokai holding me ransom for my 4 digit unlock code of my radio

I recently had my battery terminals disconnected. In doing so my code for my radio was lost. I Now have a "safe" mode radio. I asked a local garage to ask VW Barons Tokai to assist. The garage took the radio out and sent both numbers of Vin and Radio to VW Barons Tokai to look up the 4 digit unlock code. Barons Tokai declined to assist on the phone as they wanted the car to come to them ?, but only on a Saturday. I duly arrived 28.04.18 and was told that there is a charge to take the radio out and then to diagnostically look up the code. This is nonsense. They need two numbers to give the unlock code which were already supp****. I am being ransomed for a code that belongs to me. Despicable when no labour is required!