Interest charged in error - it never ends

Despite the attractive cash back opportunities/reward boosters associated with Discovery Bank, their systems and service are a constant source of frustration and completely ruins the customer experience. Since being migrated to Discovery Bank in the 2nd half of 2019, I have been erroneously charged interest on my account after a statement run on several occasions. They admit the issue on their side and reverse the interest, but the problem just resurfaces the next month again. You spend ages on the phone with them and if the call drops, tough luck you just have to call in again and start over!