Checkers Waterfall Corner sold me expired food

On 25 April 2020, I bought 4x 500g C***** Fruits of the Forest yoghurts from Checkers Waterfall Corner, JHB. When I took one for consumption today (29 April 2020), I notice that it was very watery with an off taste. When I check the expiry date, I noticed that it had expired on 18 April 2020, which was 7 days before I bought it from Checkers.

Why was this product still on the shelves for customers to buy? Why was there no notice if Checkers intended on selling expired goods.

Very disappointing Checkers, very very disappointing.