Unknown amount due after membership cancellation.

I canceled my membership in May 2023 and paid every cent I was liable for. Only to be called by a debt collector after 9months to say that I have been handed over for 140 rands. I tried calling their call Centre, nobody cares there. I ended up paying it anyway, who wants to be blacklisted for 140 rands? Even if you finally get hold of them, their consultants never call you back.