وَإِنْ لَمْ تَكُنْ لَهَا عَادَةٌ: فَنِفَاسُهَا أَرْبَعُونَ يَوْمًا.
Meaning: If she has no established habit, her nifas is forty days.
This concerns bleeding exceeding forty days without a recognized prior habit. It does not mean that a woman whose bleeding stops earlier must automatically be treated as in nifas for all forty days.