Why don't you cut the interest on account settlement

I borrowed an amount of money from credit solutions which was R30 000.00 the total credit was R41 121.79 that includes total interest R5 820.79 , credit life insurance R3 078.90, initiation fee R1 197.00 and the total monthly fees R1 026.00. with an monthly installment of R2 741.45 for the period of 15 months I paid the instalments of 12 months then I ask the settlement they gave me a settlement amount of R 7 675.19 from the outstanding balance of R8 224.39 as per statement. that makes a difference of R549.16 to the actual dept. while I still have 3 months left of credit life insurance R 205.24 a month, interest charges that I don't know and monthly fee of R68.41 a month.