A friend of mine owns this tablet and has entered the password incorrectly too many times and now the device is locked asking for a Google account. Unfortunately the Google account password is forgotten.
I figured the only way would be to factory-reset the device from the Recovery mode but when I enter the recovery mode (by holding Vol Down + Power Button) it reboots the device after a few seconds in recovery screen.
Now I'm stuck and have no idea what else to do. The tablet model is S7-931u.