BAD SERVICE

I decided to get WiFi with Vodacom last year October, they were very quick to do the order and do the installation BUT when it came to having the service active at my house I struggled. I've never had any active WiFi and when I called them to find out why?? they kept saying they see the problem and will send it through as first priority, it has been a week and they still did not get back to me and I had to follow up with them after they said it will be sorted in 24 hours. I decided to request a cancellation and when I did they said I had to pay for the installation fee. I've been trying to get their banking details since November to pay them (I tried using the banking details on my banking App but the reference they gave but it does not work) but after 2 months and sending emails at least thrice a week, still no response but yet I get an invoice every month for a service they de-activated after I requested a cancellation (baring in mind it was never active). They keep trying to debit my account every month which I think is ridiculous because I DONT HAVE ANY ACTIVE SERVICE!!