********** linked account

I am a customer on Bidorbuy for over 12 years. I have opened a business account to sell a product on Bidorbuy. When I try to load a product yesterday I got a message to contact Bidorbuy. This was the feedback I received. "I have checked and I see your account was blacklisted due to owed fees of R770.00 on an account linked to you;" I rep**** I do not know the person who placed a link on my account. The reply from Bidorbuy. "Unless he pays that money then he is not allowed. His selling account cannot even be reviewed before he pays that money." How can someone that I do not know link a account to my profile. How safe is your account with Bidorbuy and what information is leaked at Bidorbuy.