Very bad and reaping people off their hard worked money

Good day I would like to lay a complain as I am not getting proper service and worse I am giving wats app number were people just close my calls while I am explaining. On the 14 May I called cancelling my account and I was put through retention were I did explain my problem and telling them I want to cancel and I was told I need to serve 30 days notice which is starting this month and I told them to reduce my coverage from 100 to 50 which I was told that would be done and this month I will pay R689 but instead they debited my account with R1029 and when I called in the morning I was then told to send my id and proof of banking which I did via your wats app now I am told there is not refund and my account is only starting next month which I have cancelled. Their service is worse than I have ever seen in this world . For years I have been paying for less Mbps than what they promised then I am told it’s my old router while when they increase they knew I had an old router they are taking advantage and worse they don’t care as long as the my get money from you Regards Ellen ***