No communication at all

I have a debit order of R139 every month the 20th however August debit order bounced as there was not enough cash in the account. Later during the week I called and the provided me with the EFT details which I made the payment, however they still made a debit run through my account on a complete different date that we had agreed on. I have bee trying to call when selecting the accounts department the is no answer or it drops automatically. This month they tried debiting my account with double the amount we agreed on and I made a EFT again however howcome they cannot rectify all of this on the system. When calling the number and selecting for product options they are quick to answer however billing and accounts department there is no answer at all.