Mmi display control muddle

[Jimbobtay]

Hi. Any advice would help

I’ve got a q7.   2008.  The battery went flat so I connected the charger, ever since then no mmi.   
Had an auto electrician out and he fault finder the mmi display control unit but said this need to be done by Audi as it needs them to repair and recode   
also there’s a drain in the battery which means I need to charge every few days.  
So 

any advice. Thanks