Daily Briefings are a Premium Archive feature, but the app never tells you that, and that gap is causing both problems you’re seeing.
Scheduled briefings only run for Premium Archive accounts, so the twice daily setting on your premium account never fires. Same story with clicking: on a premium account each briefing only unlocks its first 3 stories, so clicking any story link past those opens a tab with nothing to show and you land right back on the briefing.
I’m shipping a fix that makes this clear. The briefing view, the settings, and the setup screen now say that automatic briefings and the full story list require Premium Archive, and clicking a locked story shows the upgrade dialog instead of doing nothing. The small arrow icon next to each story title still takes you straight to the article on the publisher’s site.