Oplus phone is powered by Mediatek chipset (MT6582). Just flashing the FRP partition will bypass the lock. Require paid softwares.
Try one of many ways to get a temporary access to the device. When you're in, do the following:
(I won't show you how to access the device. You'll have to find how to by yourself)
- Download this APK file and install it.
- When installed, open it. You'll be asked to enter your Google credentials (E-mail and password).
- Afterwards, factory reset the device (from the menu or from the recovery)
- Now when the phone boots, it will ask for Google account, enter that E-mail and password (the one you previously entered before the reset).
- Et voilà. FRP bypassed.
Use this method only if you forgot the account associated with the device. Do not use it if it is a stolen device.