In order to reset your password, you can try to turn your Tablet off. After that, hold the Volume down key pressed and simultaneously press the power key. Your tablet will enter to recovery mode and you can use the volume down key to highlight Wipe data/factory reset option. To select it, you can use the power key. By doing this, you will lose all your data and settings that had been made on the tablet. However, your SIM card data is safe.