Capitec is very unhelpful and unreliable

On 7 July I have done an online purchase. The amount was deducted from my account twice. When I queried this, they told me that the people I purchased from probably deducted it twice (one transaction went off, another is on hold as according to them the transaction must still be processed and they need to make sure that it can go off). I phoned this Company (who told me that they have problems with Capitec all the time and they sent me a statement showing that that they have only processed it once. I literally have NO money left in my account, so I phoned Capitec twice, I have sent e-mails and visited a branch the second time today. After spending about an hour there, they told me they will have to log a dispute and that it will take up to 7 working days. I have tried to explain to them that I have proof in front of me (which I left with them) showing them that the Company stated that there were no more transactions that will go through, they told me but "what if" they do. They cannot release my money. They apparently need 7 working days to investigate. So, why did they not lodge the dispute the first time I queried the transaction?? When I argued that it is not my fault, nor the Company I made the purchase from, they asked me, so who did the online transaction? I have also spoken to two other people who experienced the same problem with Capitec and they both closed their accounts afterwards and moved to another bank. I am closing my account with them. Capitec sucks!