R09813 not updating PEC to L

I am trying to use R09813 - Change Account Information to update the PEC on certain accounts from blank to L (subledger required).  I'm getting an error message "Invalid Change.  Accounts with balances in the F0911 table cannot have a posting edit code of "N".  I checked the accounts that did not update and they do have transaction in the F0911 however I'm not changing the PEC to N but to an L.  I can use the revise single account program and change the PEC to L but I need to do a mass update.  I'm not sure why I'm