Leliktec Tablet Touchscreen Does Not Work

[GERTMINT]

Hi I bought a cheap leliktec 7" Avalon Eco Allwinner A20 tablet with 800x480 screen for my son. I updated the firmware from the leliktec website as there is a known bug with iplayer. but now I have no touchscreen. But works with a mouse. I've emailed them many times but they ignore my emails. I assume I installed the wrong firmware. As I installed the 9" 800x480 version. Does any one know how I can get the correct firmware? Or if there is a fix for this? I'm a newbee to this. Thanks mark