A lack of moral fibre and ********* conduct

This company is hired by MTN to do it's debt collection. I have been on a debit order arrangement with the company until Sep-20 When the company migrated to a new debit order platform. When I realized that my debit order in Sep did not go through I called the company and made the arrangement to have my account settled I was given a settlement figure and also confirmed via email on the 2 Sep 20 as R1190.42. We entered into an arrangemt to have the account settled on the 25 October 20. The company failed to run this debit and they admitted to this via an agent Simphiwe who called me on the 10 Nov 20. The company now wants to change the settlement figure and increase it to R1500 and claim that this is legal fees. This is ********* conduct , companies like this should be ashamed of having such low moral fibre