Appalling customer services Finchoice

I am utterly disgusted with Finchoice, i have an account which went into arrears which i have a standing arrangement of R300 after the last arrangement the lady advised this will stop the calls but next month they will call again which i accepted, however I am getting calls every 1/2 hour , i have blocked the calls but they still call from alternates. I called customer care and spoke to Liana /Liama(refused to give her surname, explained I am in hospital and this is stressing me out, said she cannot make the calls stop . I said i have an arrangement in place which she picked up but said she cannot stop the call, I asked to speak to a manager and she asks what is the manager going to do. Is this how you treat clients. I hope that i am not being charged for these calls ? It seem this is the only ways you will listen to the client clearly your agents cannot.