Mishkat al-Masabih 22 Clothing كتاب اللباس 58

وَعَنْ أُمِّ سَلَمَةَ إِنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ دَخَلَ عَلَيْهَا وَهِيَ تَخْتَمِرُ فَقَالَ: «ليَّةً لَا ليَّتينِ» . رَوَاهُ أَبُو دَاوُد

Umm Salama said the Prophet came to visit her when she was veiled and said, “Use one fold, not two.” Abu Dawud transmitted it.