1.First of all Power Off your device.
2.After this just press Up Volume Key and hold it.
3.Now press the power button and hold it.
4.It will start a secret terminal.
5.You can use home button for go up and down.
6.You can use option DELETE ALL USER DATA.
7.It will take some time, and problem is solved.
Warning :- if u use this trick then the data of your mobile will be lost.
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