TFG ***** credit protection.

I once opened an account with Markam around 2007/8 while I was a student, then I used the account, but paid it off, and never used it for a number of years, therefore it was a dormant account, while the account was dormant, no fees were billed whatsoever. In 2016, I then decided to use the account again, paid it off in 2017, however, all of a sudden I am still getting billed credit protection/insurance though I do not have credit with them as my account is full paid, this has never happened before, it just started happening recently. My account is fully paid but I am still being billed credit protection, though I have no credit with them. My question is, what credit are they protecting if I do not owe them? I have explained this to them countless times and now it has affected my credit score because they did this behind my back and recording me as a defaulter.