How to add a Gnome Calendar reminder in 24.04?

Just what the title says. When I edit a (non-all day) calendar event to add a reminder (e.g., 5 minutes before event), or even more than one reminder (e.g., 5 minutes, and 1 hour before event), it seemingly does so, but when I click "Save" (1) no alarm notifications occur, and (2) if I edit such events I find that no reminders have been set/saved.

How to add and actually save and respect a reminder in Gnome Calendar events in 24.04?