MFC collections team are bullies and treat clients like ****

I took car finance with mfc since 2021 and i never missed any instalments until June when i was unwell and I called to mke arrangements to pay a certain amount until the arrears are updated, however i was told no i can't pay what i can afford i need to restructure the remaining terms when i refused i was double debited after arranged amount was paid as well, the double debit was refunded, but now am called by external collector saying they are coming to collect my car over an amount or R4500 of arrears but I have been paying the account. where are my rights as a consumer? their collection agents are rude.