Unprofessional and poor customer service

I recently got a home loan with Standard bank, upon filling in the documents we had informed them of our external insurance and sent through the detailed policy. In July I received an email from std bank saying how much I would be debited for my insurance policy with them which i had never agreed to. After many emails, the issue was resolved more than a month later, after which the money had already been debited. They informed me that we would not be debited going forward and that they approve our external policy. However we would only be refunded 50% of our debit order payment. At the end of August , the money was debited again and when I emailed them they said the issue would be resolved for the second time but I have still not heard back from them. They have also not responded as to why only 50% of our money would be refunded when the error was on their side.