Pokušaj ovu metodu, pojma nemam dal će radit na 3650 (ali na 6600 sigurno radi):

The method of performing a hard-format, i.e resetting it completely to factory defaults and removing all data, is as follows:

1. Switch off the phone.
2. Hold down the following three buttons: Green (call answer) button, * button, and 3 button
3. While holding these buttons, press the power button and switch on the phone
4. When the message 'Formatting' appears on the screen, release all of the buttons