Expired products from ShopRite

ShopRite in Durban west street which was previously Cambridge is selling us maize meal with maggots inside for 3 consecutive months the maize meal I bought from ShopRite has insects inside with colourless maggots I believe they're selling us expired products I am very disappointed with ShopRite and I have been buying my groceries from them since way back,the maize meal that I bought month end of March I now have to throw it away