I was declared bankrupt in March this year and earlier this week I received a statement from one of my creditors which gave me a total remaining on my loan. I wasn't sure what this meant and why they had suddenly sent me a statement after so many months. I started to worry that I had given the wrong account details on my orginal SOA and starting to panic, I thought I would send the statement to the OR and ask them to sort it out. However 2 days later I received another statement from the same bank, stating that this account/loan is now closed. I am assuming everything is now okay by the sounds of it and that it was just the process of account closure, which can takes months to finalise.
I haven't had anything similar but I do remember a couple of people posting similar things where creditors continued to send them updated statements. Even if they called the creditors they were told that the creditors could send them a statement until the amount they owed dropped off their credit file even if they weren't going to pay it off due to bankruptcy!
If you have received a letter saying that the account is closed the it may just have been a final statement and I wouldn't worry about it.