Complaint About Threatening and Unprofessional Conduct by Debt Collector

I am writing to formally lodge a complaint about a very unprofessional and threatening call I received from a lady who introduced herself as Pinky Hadebe claiming to represent a Russell Becker Attorneys on behalf of African Bank. The collector did not confirm my identity before discussing the alleged outstanding account, which is a serious breach of privacy. She then proceeded to threaten me with a garnish order, using an aggressive and disrespectful tone throughout the conversation.