I had the same problem all you have to is go to NET10 website. Go to technical support and since I have an account on the website, it tell me my sim number. Then you type it in the box asking for the sim number. It well then give you instructions on how to unlock!!
1. Enter 45627050 and then press OK. "Enter New PIN" will be displayed on your NET10 screen.
2. Please enter 1111 and then press OK. "Confirm New PIN" will be displayed on your screen.
3. Please enter 1111 and press OK. This is your new PIN. Please make a note of it. "PIN Unblocked" will be displayed on your screen.