Goodmorning @Parizad saremi, welcome on our Forum and thanks for your question.
If you still have a simlock on your device, you can request an unlock code via our website. You need your IMEI-number (the IMEI number is the serial number of your device. You can request the IMEI number by entering the code * # 06 # on your device, after which the IMEI number appears on your display). The application for an unlock code is free. You will receive the unlock code by e-mail within 4 weeks.
But nowadays, most devices no longer have a simlock. Are you sure it's a simlock?