Car Finance Query

I am having a terrible treatment by Standard bank at this point . I called Standard Bank Car Finance to change my debit order date to 15th every month . I was told this request will be done . To my surprise debit order went off on the 6th Feb instead of 15th Feb and was returned I did not have funds on the 6th . Now I am calling to ask standard Bank to debit 1 missed payment for Jan with the Feb payment in 15th March and Standard Bank consultant tells they are unable to assist as the Account has been handed over to Debt collectors in Mid Feb 2025 , which means 2 weeks after missing my fist installment I was handed over to Debt Collectors . I have never missed an installment since Oct 2021 when this car was purchased - 38 monthly installments made without missing a single payment , I have now missed 1 installment in Jan 2025 and the immediate action by Standard Bank is to hand the account over to Debt collectors and refusing to listen to me when I request that all outstanding amount to be deducted on 15/03/2025 and all installments to go off on the 15th every month going forward. I was told to contact Debt Collectors . Please advise if this is how loyal clients are treated as soon as they miss one payment ?