Unsolicited autodialler phone calling

I keep getting unsolicited calls from the number *** to my unlisted Telkom Landline. When I answer there is no response and the person or machine on the other end simply hangs up. I called the number and ascertains that it belongs to The Touch Down Group. They are apparently situated at 23 Morris St. East, Woodmead Exchange Building Woodmead, 2157,<br> South Africa. Should I receive another such unconsolidated call I shall report this to the relevant authority as it is a breach of a number of statutes. I have no prior relationship with this company; have not given them permission to contact me and have no interest in anything they are peddling.