48 month loan that i need to pay for 8 years. Day Light *******.

I took a loan with Capitec Bank in 2014 it was for 48 months for an amount of R56000 where my instalment was R2000.00. So in 2016 i called to reduce my amount to R1600.00,ever since 2016 I am paying the 1600.00. So when i contacted customer care after i saw on my app my outstanding amount is R37000.00 but the remaining instalments was 40. I contact customer care and the lady advised me that the R1600.00 that was debited in the month of July R1011.85 was for interest and the 500 was towards the loan amount am very unhappy when I contact today they provided me with a ref number ********** 1. If you can calculate R1606*40 it means that i still owe them R64240.00 after paying for 4 years already even if I reduce the amount to R1600.00 this is day light *******. I need answers am not going to leave it like this because of a R400.00 difference i need to pay for another 3-4 years am earning lesser. Please get back to me I am going to post it everywhere i can’t afford to pay this much. Im Very dissapointed in Capitec hence they say they interest is the lowest. Account Number: ********** 994