Need help for chinese tablet (rk2926)

[Marin Uzunov]

Hi everyone!!! My english is not very well but, i try to explain what is the problem! I have chinese tablet ALFA e-Tab2,( http://alfaseries.com/alfa-e-tab2.html ) this device work one year fine but my son reflash wrong firmware and now... not work!! Display is black. When i connect to PC and pres vol+ and power botton i see in device menager rk292x device...
Help me to fix this tablet... and excuse my english, i am bulgarian...