Auto Reboot/ Auto lock Solution Yureka, Yuphoria

Procedure:

1. Go to settings, then open themes. Now just select default theme.
2. Go to accounts in setting and delete your Google account and Cyanogen account.
3. Not go to apps in settings and find Google app. Delete all data of Google app.
4. Now delete all data of Google play Services.
5. Now tun off your phone.
6. Long press volume up + Volume Down + Power button, All together.  Now you system will boot to recovery mode.
7. Select Wipe catch partition. It will take 3 to 4 minutes.
8. After wiping completes. select reboot system now.