Line running at entry level but paying for 4MBps l

I have been struggling for 48 hours with a line speed that drops as low as 189 Kbps! That's slower than a dial-up and I queried this more than 24 hours ago but am still waiting. Cannot do any banking,cannot deal with my e-mails and need to resolve issues online that also cannot be done but I'm paying for a 4 MBps line. This is the umpteenth time and Telkom can't be bothered to sort it out.