help with my chevy malibu?

[hhhbk 4 life]

usually when i turn off my car the radio stays on until i open the driver's door, and today it wouldn't turn off, since i didn't want for the battery to die i just disconnected the battery but now that i wanna turn it back on it wont let me and on the radio it says "Locked" does anybody knows why this is happening?
and what do i need to fix it or who should i go to?

 

[ZEDMILLY]

call your dealer,they have to call in to get code to release theft feature.