Standard won't refund my money

Can someone please explain to me why I have to phone standard bank to remind them that they took my money ********ly and I need to be refunded. If the tables were turned I'm sure I would have been charged interest had numerous call centre agents phoning me about the money, why should I take time off from my work because of your staffs incompetence. I have spoken to 5 people none of which got back to me which makes me wonder what happens to people who've changed their cellphone numbers and the elderly. This is very disturbing to think STANDARD BANK could be taking monies from people and they are not even aware of it. shocking especially from such a big instution that is 'supposedly" MOVING US FORWARD. Each time I phone I keep being told there is a technical issue 2 WHOLE WEEKS I have been told this. I sure hope where ever it is it generating interest as it would have done if the tables were turned. DO THE RIGHT THING