Never use Rain as an internet service provider. Horrible services

I’m have received the worst service from rain for t he past two years. Last year o decided to cancel their services because they couldn’t solve any of my problems. They sent a courier company to fetch the router and SIM cards of which I gave back. Since then I am receiving messages about paying my bill or they will disconnect my services? How do they disconnect a service I cancelled and their courier guys collected t it devices. Every month they try to debit my account without my permission. They are abusing me with endless email, smsed, whatsapp messages. I have to lock my cards from Nkume purchase because randomly n is always trying to collect money from my account. They collects money ro a few months even after I have cancelled the service and they want to continue. I’m advise anyone not even think of using rain because they are operating low the ANC led government which always straps from the people.