Sometimes documents are created after the certification period is open because the account has recently been marked for as an account that requires certification. Check with the FAMIS or EPIK account setup staff to see if the TE Certify flag has changed recently.
The FAMIS mainframe screen 886, Account Audit Trail Inquiry, can be utilized to view changes to accounts. In the example illustration, below, the TE Certify flag can be seen to have been changed from Y, to N, and then finally to <blank>:
