Product disappear and staff unable to provide any reason

When Pick n Pay sell a product for years and suddenly one day it just disappears and the staff just pull up their shoulders, I get really irritated. For years you have been selling Toni Glas 1.5 litre tonic water; an then suddenly it's nowhere to be seen. And your staff honestly should know the products you sell and be able to provide a valid reason why it is suddenly not available anymore