Relentless spam calls from Telkom

Everyday I get about 10+ calls from the following numbers *** / *** which show up as Telkom Sales numbers in True Caller. I have blocked these numbers but it still shows up as missed calls.

This is very irritating! Can you dumb ****ing ****s not get the ****ing picture? Go back to ****ing school and learn something you illiterate retarted ****ing pieces of ****!