Android has its own list of blocked numbers, used by your phone app for calls and by other messaging apps. 1krBlocker can add numbers to it.
Turn on Also block those numbers on this phone in Settings: Adds numbers you or 1krBlocker block to Android’s block list, which your phone app uses too.
In Trusted & blocked senders, such numbers show Also blocked on this phone. Numbers you or another app blocked in Android's list show Blocked on this phone by another app or by you; stays blocked there.
Unblocking: removing a number in 1krBlocker also removes it from Android's list if 1krBlocker added it. If someone else added it, 1krBlocker leaves it there; remove it in your phone app (Settings → Blocked numbers).
Sender names (like "InfoSMS") can't go on Android's list; 1krBlocker blocks those itself.