Vodacom bad service

Vodacom worse service ever. I got billed for a service I did not get. I cancell my contract with vodacom because 2 months after fiber was installed I struggel to get conected. All the people around us with other service providers was conected but not us. So I decide that after 2 weeks of daily phonecalls for conection, and I did not receive any service I cancell my contract. I do have sr number for my request. My monthly bill was supposed to be R650 monthly. I receive a bill for R1020 for no service and the bill status line rental. How is it possible? I will never takeout a contract again with Vodacom