Russell's Acc- Bad Debt Written Off

I don't understand, I've been paying for my Russell's account since last year and when I checked my credit report this year I realized that the status was Bad Debt Written Off, while I've been paying for this account, the balance is also not going down but the debt was written off. What actually goes on here and according to the credit bureau, a default only stays for one year before being removed. Any reason as to why I'm still paying for something that's not decreasing when its already written off? Please update your systems accordingly.