also if i m not a php expert i find the problem...for some reason now the sql db now do not updates manufacturer id into product table of the db...as i have modified the value to the correct manufacturer id (was set to 0) the manufacturer box restart to works correctly, it is a little boring to modify this for each product i ll add in future but better something that works correctly without code modifies that could create problems...
thanks anyway for this contribute that resolve me the problem of vendors sales stats.