getting statements for closed accounts

I have in writing from ABSA bank that an account I had with them was closed and paid up. This morning I received a statement for this account, that I cant even open. When I tried to find information I was refered to 3 different departments and the account cant be found on the system or wait here it is. How can it have a balance if the account was closed? And not to mention the employees that shunts me from pillar to post.