The way in which you add courses has changed in 2023. When adding a course manually, this now occurs on course-level instead of activity-level like before.
Previously, courses were added based on (for example) the work group or the lecture. It looked like this:
Since 2023 courses are added based on the overarching Y-number, which includes work groups, lectures, et cetera. It looks like this:
On the right side of the screen you can also see this difference:
