Account Paid up but getting calls

Hi, my Virgin Money Credit card was paid up almost a year ago (it was originally handed over to Attorneys for collection). I had a Debit order that went off every month and around Jun / Jul last year the account was paid up. I received no paid up letter or anything. Now I'm getting calls from lawyers again saying I'm still owning money on the account, ALMOST A YEAR LATER!

Can the account please be closed and any outstanding fees reversed?