As noted above, Facebook imposes a "cooldown" period. You cannot toggle blocking on and off rapidly; you will have to wait the mandatory 48-hour window before the system allows you to block that profile again.
Two years ago, Mia blocked Jake on Facebook. Not because of a dramatic fight, but because of a slow, silent drift that soured into annoyance. He posted too much about his keto diet. She got tired of his political rants. One Tuesday night, after a bad day at work, she saw his comment on a mutual friend’s post—something harmless but irritating—and clicked Block . It felt satisfying, like slamming a door. unblock someone on fb