Wesbank Service Plan Cancelled Refund Horrible

Very bad service received from Wesbank, I have a vehicle which is financed by Wesbank and I took a Motovage service plan through them last year in November. The total amount of the service plan was R26000 and I used it only once when I service my car at GM, the service cost was R3500 then in January 2021 I cancelled it. It took Motovage three months to finalized the cancellation and they sent me an email that confirmed that "The Wesbank account will reflect arrears of approximately R12 064.20 if SERVICE PLAN cancelled." I tried to get more clarity about this matter and Motovage keeps on referring me to Wesbank for financial related matters and I called Wesbank Account department to get assistance and to know exactly why are they charging me this amount for and no one ever give me clear explanation. I ended up being so frustrated because they even not ashamed to call me and remind me that my account is on arrears, for what. This is a day light ******* as a big financial company like Wesbank which fails to handle this kind of issues, I regret taking the vehicle finance with bad service providers who fail to attend to their clients. I will not pay any installment until this issue is resolved and satisfied with the answer I will receive. I rather cancel the vehicle contract as they fail to give me answers and I will not pay any charges.