The cover page in School > All Staff > Cover will show you lessons and registration in line with the Timetable Periods set up at your school. You can see more details on managing cover here: How can I manage cover?
This means that if registration or certain lessons are missing from this page, you'll need to check your Timetable Periods set up here: Timetable Periods. In the example below, registration is missing because it runs 8:30 until 9:00 but the timetable periods only start at 9:00.
You might wish to set up an additional period for each day for Registration, this will then show on the Cover page.