Terrible service from Standard Bank Insurance

I requested to change my debit order date which was agreed to over the phone. Not long after this I was notified via email that an amount four times my usual monthly premium was to be deducted from my bank account. I immediately called and was informed over the phone that this was an error on their part and that I could ignore it. I have subsequently been debited for this ridiculous amount, in addition to my usual monthly premium. The two amounts have been deducted all at once. Clearly not an error then. I expect a phone call to resolve the issue in the morning or I’ll be cancelling my policy. This is unbelievably bad service.