help please, mediapad t3 stopped working

hi all, i really need help. everytime i try to turn my ags-w09 on nothing happens until i put it on to charge, then the screen comes on and says "your device has failed varification and may not work properly, to learn more visit web address that is no help at all when i go to it (1) press power key to continue (2) press volume up key for 3 seconds to enter erecovery to restore your device (3) our tablet will continue to boot 5 seconds later if there is no operation* none of these things work and i'm stuck, please help.
thanks i advance, jo.