Useless Administration

Telkom calls me daily, and I mean DAILY!! asking to speak to my ex (he rica'd my sim card in 2017) I have told them since 2019 (when the contract ended) that this is no longer his contact and they need to contact him via his alternative number (they have this number as they have confirmed it) and have assured me countless times that they have updated the system blah blah blah but then very next day they are back at calling me ALL day! this has been going on every day since 2019! Does noone know how to do administration there??