FNB - How can we avoid helping you?

I made a purchase from a company for R60 in March 2018. 30 March 2018 another payment for R1201 went through for this company, even though I had still not received the items for the R60 order. The on 18 April 2018 another R1289 payment went through on my account for the same people. I queried this with my private bank. He then sent me the documentation to dispute the charges to complete. After two weeks when I contacted him, he notified me that the dispute had been declined. I then requested by who it was declined and on what grounds? He then informed me that it was declined by VBS because the documents which I sent them were not the correct documents????? I then advised him that these were the documents which he had sent me to complete!! I then requested that the correct document be sent to me. I then completed these documents and sent them off to the private banker again. It has now been a week since that was done and I still do not have my money back. To top it all, last night (17 May 2018) these people debit my account with another R1,348. So in total I am now R3,838 out of pocket and FNB are doing nothing to cancel these transactions and get my money back. Is there nothing I can do do stop these people *****ing my money? Will I be forced to close my account with FNB to stop these *******? Maybe I should have just stayed with Nedbank, at least when something like this happened it would be sorted out within a day. :-(