Fundi still deducting even after student loan has been settled in full.

I’ve finished paying my loan in 2021 September or so yet they still continue to deduct, I called them to cancel they said they will cancel, so December I went to stop the debit order at the bank and in January I received an sms saying the debit order has been activated. I’m so annoyed and angry coz I don’t know how long they plan on deducting and why if the loan is already paid up.