If you can't gain access to your Android device due to forgetting the Voice unlock, PIN, pattern lock, slide lock or password protection then here are some methods you could employ. some of these methods will also teach you how to hack and bypass Android Password/Pattern/Face/PI
Unlock using Google account
If the Android device is associated with a Google account then simply supply your credentials to regain access. If mobile network data isn't enabled then you can use WIFI. WIFI can be enabled in ABD ( *Note: USB Debugging needs to be enabled).
In ADB, type:
adb devices then press Enter
adb shell svc wifi enable then press Enter
Wipe pattern in adb
* In adb, type the following
adb devices press enter
adb shell press enter
cd data/system press enter
su press enter
rm *.key press enter
* Now, remove the battery then boot the phone.
* If presented with a lock screen, just enter any pattern and you'll be granted access
Source: How to regain access to an Android device after forgetting pattern unlock / PIN