I am from Pakistan I had a Samsung S3. PTA(Pakistan Telecommunication Authority) has blocked my phone. I am receiving this message "blocked SIM". I have change 4 sims card but displaying the same message. Can someone tell how I unlock my device?
Charge the phone to 100%, reboot phone.
After the reboot open the battery calibration and push the calibrate button.
Than use the phone until it reach the 0% and charge it until the 100% with the phone off.
And you're done.