Harassment by Home loans department

My home loan debit order was changed from the 31st of each month to the 3rd, after the agent said that I can't cancel the debit order as I have been making EFT payments since the beginning of the year. I doubt a month goes by without receiving smses and calls stating that my account is in arrears because the debit order was missed. I constantly have to explain to rude agents that I had made a transfer of x amount, on x date of the month. Recently I was told that the debit order can be cancelled and this request was logged. I received another call from the rude agents, this one's name I note (Tamara), who insisted that I owe money for June because the debit order for June was missed on the 3rd of June yet I made a payment on the 1st of June. She tells me that the payment on the 1st was for May which I pointed out that a payment was made on the 2nd and 4th of May for that month. She eventually ended this debate by asking me to confirm my email address and saying goodbye, no confirmation of making a correction. My request is for their systems to be updated and not receive calls from rude agents fighting with me on misinformation.