Getting Cannot Reschedule error trying to reprocess Open Enrollment

Getting error 'Cannot Reschedule - Notification Completed' when trying to reprocess the Open Enrollment event for the schedule Id selected. I'm getting this error using the Schedule option in the OE/Snapshot tab under Reprocess. The schedule has already been finalized but we need to do this in a test environment.

We are troubleshooting an event rule that terminated some pension plans when the Open Enrollment event was finalized. This is another situation, but what is needed for now is to be able to reopen the Enrollment for that schedule Id.

Any help will be appreciated.

Thanks