Yo
I had the same problem recently. Applied for the 3 month trial and my speeds were exactly the same as yours. After numerous phone calls and them telling me that my line is fine, I checked the form I received from Telkom containing my username and password and guess what? It said 'Product details: TI DO Uncapped BASIC'. I was so eager to get home and try out my brand spanking new Internet connection that I hardly even looked at the piece of paper when I got it. However, I don't get how someone can be so incompetent signing me up for a 384Kbps package when I explicitly asked for the TRIAL which all Telkom employees should know by now is meant to be 'Uncapped Advanced'. So eventually after visiting one of their branches and having them cancel the Basic package and signing me up for the Advanced instead, I am now more than happy with my speeds
I would suggest going into a branch and have them check what package you're on.
Cheers