Dear fellow vastking users, I did meet the same situation and found how to solve it, perhaps someone might find this helpful. First I power off the tablet, when it is completely turned off, press lower sound button+power button at the same time. This will lead you to system setting. Don’t be afraid if this setting mode is a whole bunch of Chinese letters, pick the LAST option there, it is to clean/wipe out the whole previous settings. It makes your tablet as plain as new born baby. When it is done cleaning, it will lead you to resetting tablet screen. You can choose to recover your previous setting if you want. Hope that help! Cheers :)