2 verses have
وَكُنَّا
in Edition Uthmani / Al-Muddaththir (The Cloaked One)

45:74وَكُنَّا نَخُوضُ مَعَ ٱلْخَآئِضِينَ

46:74وَكُنَّا نُكَذِّبُ بِيَوْمِ ٱلدِّينِ