Milk gone off way before best before date

Complaint here is same as most of the others, its about the full cream milk, the milk has gone off before the best before date, the date on the bottle says 6th December, but today is the 2nd December, so maybe they were getting rid of the stock because they were selling them @ 2 for R50 at food *****s, this is not the first time this has happened with this milk, well trusted brand, but now not anymore.