Undeliverable customer care email

Purchased MBrand milk from Makro Opened the first 2 boxes for baking and did not taste the milk itself. Opened up another box for our tea and coffee and realised there was a faint aftertaste Opened up another box and realized it had the same problem As I am 70 km away from my nearest store and only go in on a weekly basis, I used the Customer Care email address Got a message back to say that it is not recognized as my email is not on the internal mailing list. How is this a customer care email and you cannot use this form of correspondence