Unauthorized debits by Nnimble

I tried to reach out to Nimble group about my debt/loan that was listed by Capitec back in 2019. I opened a case of ***** that never yielded fruitful results. Now to my surprise, last year, I don't know how they obtained my bank account and started debating a sum of R800. I think this is a *****ulent action and I've been trying to get hold of them but in vain. Also, this falls under a prescribed debt