Sharing of clients personal details.

I raised the following complaint with no answer to date: Upon registering my details on SSDA website, I received an email to confirm my email address. When clicking the link, it opens up a page on SSDA website to confirm personal details. The only problem is that the details I have to confirm, are not my details. I received another clients personal details which I am not able to change to my own. I have their name and surname, ID number, Address, contact number and even their employer details. I contacted the call centre on 3 different occasions, only to be told that they will send me an sms to make payment to a reference number. Now it seems my details are mixed up with another client's details and I told them I refuse to make any payments untill my query is resolved, but still, they debit my account. I tried to further my query to management and also sent an email through their website, still no luck. I am not willing to pay off another client's account and I am very worried that my personal details aren't safe with this company as they are paying absolutely to attention to my query with regards to them sharing anothet client's personal details with me. All I'm told is to make payments. I'm certain this does not comply with the POPI ACT. What do I do? Contact the client who's details I keep receiving directly and inform them about the situation? This company is highly unprofessional.