Rain *****ing money from clients

I have been using rain network for years now and recently decided that the payments are too much and that I couldn't afford it anymore. I understood that the way they work is pay first and then you are connected to the network. So for the past 5 months I've stopped using the network data. I've even disconnected the router power supply. But now they expect a payment of R2500 before I can even cancel and return the router. How is it that I'm being charged for data ,absolutely nothing used. So what exactly is that money for? This is consumer abuse. We cannot allow a network to continue *****ing and abusing their platform. I've even spoken to the call centre agent to have the router picked up, she told me that I first needed to pay the full amount due and if not, then rain will continue adding R600 a month until it's all paid up. I mean ***.