Vodacom no customer service incorrect billing and the list goes on

Vuma came to install Fiber on Saturday 30th June 2018, we switched it on for first time on Sunday 01st July 2018 as they firstly delivered to the wrong place and when they first installed they did it incorrectly and there were no signal and it was to far away to get signal

We have been phoning non stop but to no avail,the problem is they billed us over R3000 we need the invoice to be rectified as it was free installation, first contract was for the special of R799 pm 20/20 mbps then they said they made a mistake and it's R849pm free installation as we are an old customer and that was the special running as it was new in our area. When the accounts department calls us they insist we call them back we cant get this sorted i do keep their calls recorded and need to know how we can just cancell and rather go with someone more reliant and who cares about their customers cause they most certainly DON'T.

Maybe we need to take this further , at least Telkom had better customer service.