The banner "Notifications are off. You won’t hear about new messages, or about links found dangerous later." means Android isn't allowed to show 1krBlocker's notifications. Messages are still checked, but you won't hear about new ones, or about a link that's found dangerous after a message arrived.
To fix it: tap Turn on on the banner and allow notifications. If nothing happens, open the phone's Settings → Apps → 1krBlocker → Notifications and turn them on.
Which notifications you get: safe messages and those with a warning notify as usual. Quarantined messages are quiet on purpose, and very risky ones make no notification at all; they're counted in the daily summary instead. You can change sounds per kind in Settings → Notification sounds and channels.
Notification texts for risky messages never show the link, so you can't tap a scam from the notification.