in SN0028 1%-Goods at Reduced Rate
Certain essential goods, such as baby milk and books, are subject to a reduced tax rate lower than the standard 18% when sold to end consumers. This preferential rate is intended to keep vital or socially important products affordable. Retailers selling such goods must ensure that the products are correctly classified under the applicable tax schedule to qualify for the reduced rate.
so why you are adding any other tax even its 0.