The corporate management company should be able to help you. I would call them, let them know whats going on. It just might be on their file. Look for your copy when you can. I would send in the rent you think you should send, and let them take it from there. Make sure you write in the memo on the check, last months rent paid in full. If they cash it, there will be nothing they can do, if they don't, it will take months to go in court, and you're going to win anyway, so let them waste their time.
This is why we do our own apartments, we know whats going on. When you have a management company things get lost.
Best of luck to you!!!!
