What is wrong with the big banks?

Morning all. THE WORST. After 25 years of paying a home loan it was finally paid off in October 2019. With a credit balance of 3k. On the 1st of Nov 19 a mail was sent to mr Tobias at the relevant dep after telephone and emails galore. That the insurance was with a other co Old Mutual. After three weeks nothing was done. I contacted Hannes Gouws and got the ball rolling. Mr Tobias sent the cancellation and paper work figures to Gouws giving him the authority to do the cancellation. Met with Gouws on 21 Nov. In 5 months I cannot get the correct cancellation figures to pay. Apparently mr TOBIAS did not send the notice of cancellation of insurance to mr Gouws? Surely that is part of the Banks paperwork. I told Gouws at the meeting of 21 Nov that the insurance was switched. After the bond was in credit the insurance premium from Standard was trebbled.....Now these guys want 8000 from me excluding the cancellation cost. How can the Bank just carry on *****ing my money? A similar insedent happened 15 odd years ago ehen they put the insurance up in one year by 400%. Cost me 100k over some years. Had meetings with this same Gouws and the bank and it ended up that I had to take them to the high court. They made me a little offer to accept in a few days or lose it. Did not accept it. But the premium was dropped to only the yearly increase for that year. THEY ADMITTED THAT THEY WERE WRONG. But refused to pay back the money that I overpaid. Is this a *****ed STANDARD BANK??? I surely have the proof on paper. How many other people are they doing in with lawyers on their payroll by the likes of the guys I have to deal with??