Although it's not yet complete, the flow of energy from the forehead to the back of the head and to the throat has improved slightly, and the stability has increased compared to before.
In particular, the space between the nostrils, the lower lip, and the space between the lip and the eyebrow has widened, and it seems that energy flows more easily through the front and center of the face, from the neck to the space between the eyebrows.
This place, where I used to meditate, made cracking sounds and moved. However, in the end, it wasn't just a "crack" sound, but the entire area around it seemed to loosen like cartilage, as if something suddenly gave way during a stretch, deepening the stretch. Or, like a landslide on the seabed causing an earthquake, the entire area loosened with a strong but slow movement, and this part opened. As a result, energy became easier to enter from the throat area to the area between the eyebrows.
...After about 1 to 2 weeks, when I observed the situation, it seems that this area is not yet completely open, and it still closes during the night. However, it seems to open when I meditate. Therefore, after initially opening widely, it sometimes closes slightly, but gradually the opening becomes more stable.