Portfolio Recoery is a CA maybe thats the reason for the score drop. However, check the account their claiming i've dealt twice with them, not very nice individuals. Anyhow one was from more than 7 years and the other one is from 5 years. Didnt stop them trying to collect and so on. Eventually the really old one came off when I disputed it and sent numerous faxes. Good luck!
Starting Score: 536