BLTouch is tricky. If you move not fast enough away it goes into error mode (blinks). Even if you untrigger it holds the signal 100ms, so if the untrigger test comes to quickly you get the not untriggered message. Easiest way is to increase z probe bed distance so it takes longe to move up and hence should have enough time to unttrigger. 1-2mm more should suffice.