Making a willing payer unwilling

Long story short. My wife had to change employment middle June as the previous company couldnt afford salaries, in this times alone is a miracle. Her salary date changed however from 30th to 15th. Having started only on the 10th her 1st salary would be 15/07 She changed her deduction dates with FNB, SA Homeloans and the MFC. All three companies she had to sent through proof etc. which was done. All three came back and confirmed it changed to 15/07/2020 but as is fair there would be pro rate interest charges for 30th till 15th no prob. Come the 29th THE MFC decided to launch a debit order unsuccessful as there is NO FUNDS. We contacted them the same day and the lady said it is because we requested the change to late to stop the debit. Not sure how long the lead time is but it was requested roughly the 16-17th but she will sent it through to rectify. Low and behold this morning arrives a s129 letter of payment demand. SO again we phone and now the account is in arrears because the due date is 30/06 and then 15/07 ***. So 2 mayor financial institutions gets it right but the MFC part of Nedbank does their own things after accepting the changes. Now the profile is stuffed up at the credit bureau and mr Jose threatens us that if we dont pay MFC will double deduct. Good luck, this story will be forwarded to every social platform, NCR Credit Ombud and I will now escalate the stuff up they made with my extended motor warranty as well....