Empty 500ml Black Label cans

Hi. I bought a case of Black Label 500ml cans in the beginning of December. The first 6 pack that I opened was perfect, as always but the second 6 pack that I opened had one completely empty, undamaged and sealed can inside. Another can in the same 6 pack had a whole in the middle of the can and the beer was half. I have tried to phone the customer care number to complain and get refunded for the 2 beers or to get them replaced, but the number doesn't work or just keeps on ringing. I only drink Black Label, but I am really disappointed with the service and the brand.