Rotten product

Regular user of C&B mayonnaise. Bought 790g bottle at PnP Stellenbosch Square. Upon opening it blew due to pressure from fermenting product, one could see the bubbles. Returned it to PnP who replaced it. Second bottle even worse, it overflowed when opened. Called C&B helpline, held on until call dropped. Called again, held and eventually selected option to leave message which has not been responded to after several hours. Called again, held on and eventually left another message with no response.