Hi I have correct code for the radio (recently battery was flat) i input the 4 digit code pressed ok and it's saying incorrect pin and locks me out on a timer the code is correct in my book there's a sticker with it on so why won't it work? Iv tried turning the unit off but it won't turn off Iv also tried disconnecting the battery again and trying the code again it's having non of it any help would be appreciated

thsnks