Your tablet device needs to be reset.
Tap [
Apps & Widgets] - [
at the bottom of the menu on the right.
All data in the data storage area is deleted, including the Google account information, the system data and
settings, and any application data you have downloaded.
It is recommended that you make a backup copy of important data because the user data cannot be
restored after being deleted.
The tablet device restarts automatically.
Settings] - [Backup & reset] - [Factory data reset], and then tap [Reset tablet]