foreach ( var product in listInSql)
            {
                product.listGroup.Reverse();
                foreach (List<string> category in product.listGroup)
                {
                        var itemCategory = listCategoryInSote.SingleOrDefault(x => x.idCategory == category.ElementAt(2));
                        if (String.IsNullOrEmpty(category[2]))//kategorie po id nie ma
                         {

                            ///DODANIE WAROTSCI

                         {
                      category[2] = parentId;//Dodaje do aktualnego produktu a potrzebuje do wszystkich
                      var listInSql =   listInSql.Where(S => S.listGroup.ElementAt[0] = category[0])
                     .Select(S => { S.listGroup.ElementAt[2] = category[2]; return S; }).ToList();
                        parentId = parentId;
                }
            }