Stop ******* interest rate increase and return my money

Standard bank has *******ly increased my interest rate when my bond went into arrears as a result when calculations are done, it was discovered that Standard bank owe me a lot of money due to these ******* interest rate increase. I would like Standard bank to do their calculations and return all monies owed to me and bring my account back to normal. I am deeply disturbed and disappointed with this kind of behavior from a bank I used for so many years. Bank that I also worked for 20 years of my life. Please do recalculation and refund my money. Home loan account number: ***