Incorrect cellphone number

It appears that MBD have the incorrect cellphone number for an individual who has bad debt on a Standard Bank credit card. I have been harrassed with threatening sms messages for over 2 months now. On 20 July 2021, I spoke to Mathabo Mokoena who logged a request to remove my number from the system. on 26 July 2021, I spoke to Sanele Vilakazi who claims that they first need to investigate to ensure that I am legitimate and not linked to this particular bad debt? Sanele also claims that it takes 30 days to amend an incorrect cellphone number on the MBD systems? This is not acceptable and is also in contravention of my rights under POPIA. I expect a letter of apology from MBD and I expect my cellphone number to be removed from the incorrect debtor with immediate effect.