Forgot. Key pad lock how do I fix it

i apologize for being the bearer of bad news, but unfortunately, this is a security protocol to keep end user data safe. in order to use this device again, you will need a factory wipe.

To do this

Press and hold Power, Vol Down, and Home button all at the same time

Let go when you see "Recovery booting" at the top left corner.

Factory Data Wipe, Factory Reset, Or the likes will be option you select,

then select yes.

This will wipe ALL USER DATA, and make it as if it were out of the box.