Sa Taxi Finance ripping us off

We purchased a quantum in 2020 by them however with covid we went through struggles to pay the van eventually my husband got it right to pay what we owed them to get straight he phoned say said we not longer in arrears mind you they don't send statemmet so we don't know how far we are nothing! Bottom line they added an extra years to our 60 months which mean we paying 8 years on our quantum . the worst part is that my husband has been paying extra on account and as of now he is having a credit balance of 140 000 plus on the account but when he wants to settle he is being told that he owes 120 000. When we questioned them they gave us a runaround telling us that our account is with legal so they still have to calculate legal fees of which that was the first time we heard of the thing that our account has been handed over to legal. Our contract stipulates that the end time of the account is March 2025 and my husband tried to cover even for the Covid months they were given. how can 3 to 6 months of covid relief accumulate to almost three years even if the customer is paying. Even with the first taxi we settled we encountered the same problem but ended up paying but this time hay this is too much.