I was called regarding someone else's account

I was called regarding someone else's account. I wasn't asked who was speaking. I was just said hello Mr...... How are you. I responded I'm good. Then the female agent goes on by saying I'm calling regarding your mtn account regarding a discount given. And personal information regarding a customers account was given to me. There was no security check done in terms of date of birth confirmation. I'm talking from experience as I had an account with another collections company (mbd) where everything was done and it guarantees my person information was not disclosed to a 3rd party. When I tried to explain to the person that called that I wasn't the person she's looking for. She shouted at me and dropped the call while I was speaking. This is firstly non compliance with the popi act. And Secondly unprofessional behavior by the relevant agent. Thank you.