incorrect interest rates

I signed my mortgage loan at a rate of 8.76% in September last year. Interest rate went up in November with. 25% and then again .50% in January. Total of. 75%. So my new rate should be 9.51%. But according to Absa homelaons call centre, the rate of 10.25 they are now charging me is correct. How does that work? Can they just put up rates as they want??? Then they don't even call you like promised, but sends a sms. So regretting takngbthe bond with absa. Should have stayed with Fnb.