Absa is the most unhelpful bank

We have being home owners since 2007 and we have had a home loan with Absa. My mum and I co-own the house. My mum has being temping and did not have a permanent job, and when she finally got an permanent job we decided to change our debit order date from the end of the month to the 3rd that was back in 2012. It was initially fine and the debit order went off every month. In 2014 we started get threatening calls from Absa Collections saying that we are in arrears and we better pay our home loan or else our house will be taken, and still every single month Absa have debited us and never have we being in arrears, so we do not understand. We called the call center countless times with promises to call us back, we went into the bank and were asked to sign documents because they had made an error. The harassment never stopped, we still get calls threatening. We went to see the manager at Creasta Bank, she promised to look into the matter, till to this very day we are waiting and that has being a month ago. I'm so disappointed in this Bank we have even considered changing banks, imagine paying every month and this is the service that they provide. Pathetic to sat the least.