·lf you write, "die of disease" with a specific disease's name and the person's time of death, there must be a sufficient amount of fime for the disease to progress. If the set time is too tight, the victim will die of a heart attack after 6 minutes and 40 seconds after completing the DEATH NOTE.
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀デスノートに病死と書き、病名と時間を指定をした場答、
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀その病気の進行に必要なだけの時間指定がされておらず 無理が生じると、
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀書き終えてから40秒後に心臓麻痺となる。

·lf you write, "die of disease" for the cause of death, but only write. 2 specific time of death without the actual name of disease, the human will die from an adequate disease. But the DEATH NOTE can only operate within 23 days (in the human calendar).
This is called the 28-day rule.
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀病死と書いた場合、病名を書かず時間指定をすれば、
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀じかんどお その時間通りに適した病気で死ぬ。
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀デスノートで操れる死の時間は人間界単位で23日間以内である