Hi,
Is it possible for a Factory reset, then, do a hard reset.
The data existing in the device will completely lost.
Method 1,
Switch off the cell phone.
Press and hold Volume Up + Power button for about 15 seconds, and until you see Android recovery menu.
Then select "wipe data/factory reset" using Volume Down to scroll option, and press Power button to accept.
Browse to option "Yes-detele all user data", and confirm that with Power button.
After that press Power button to accept option "reboot system now".
Done!
Method 2
Go to any Android device that is installed Android device manager.
Open Android device manager and sign in
Select " guest" option
Sign in with the Google credentials that exists in the problematic device.
Select erase data.