Balloon account that i didnt sign with MFC Account

Hellopeter, in 2013 i took finance with mfc to finance my car. in 2017 i had financial crisis, so i decided to go through debt review, after months i decided to pay MFC directly. on July 2019 where i thought i have finished paying my car, i receive a call from MFC, that i am owing MFC R58000 with balloon account., when i question the consultant saying but i did not sign for balloon account on my mfc account, they threaten to reposses my car. i need help because regarding my account with the debt review and MFC.