need unlck code for panasonic stereo cq-vd6505u?

[Jennifer]

i bought a stereo that was working just fine till me and a friend diconnected it from the battery and then when we turned it back on and it was asking for an unlock code and i called the original owner and he said that he had never used a code for it now i need help in getting it unlock if someone could help me in getting it unlocked. thanks