Security Code on Car Radio - Frustrating

I bought my Volkswagen Vivo in 2017. I was never informed that I need to have my car radio security code. Neither was I informed that if and when I replace the car battery that the I need to put the security code for the car radio. After several attempts on my own try to figure this out, just to discover that I do not have a security code. I phoned McCarthy Menlyn, where is was informed that I can bring in my vehicle and that the they will assist with the security code on for free on my vechicle. When I arrived Saturday 6 April at McCarthy Menlyn, only to hear that they do charge R600 to do the security code. The manager on site came to assist to tell me that I have locked the security code on my car radio. Need to leave the radio on for 45 minutes, Then bring back my vehicle and they will unlock the radio and put in the security and then I have to pay the R600. I was never been informed about this, and why was the security not written in my car manual.