Simply can't cancel my Telkom internet.

I canceled my month - monthTelkom internet in April 2018 already, and since then I kept on receiving invoices. I have used all available channels to cancel, but nothing works. I kept proof as much as I could, but they just don't listen. Now it seems they handed me over to debt collectors. This seems to be a common case with a lot of people. Class action law suit?

Even when I contact them at this moment, they recognize their mistake, but still they handed me over to collectors! Now I have to struggle to get rid of them. I am seriously looking at my legal options!!