ذَٰلِكَ بِأَنَّهُمْ ءَامَنُوا۟ ثُمَّ كَفَرُوا۟ فَطُبِعَ عَلَىٰ قُلُوبِهِمْ فَهُمْ لَا يَفْقَهُونَ
Zaalika bi annahum aamanoo summa kafaroo fatubi'a 'alaa quloobihim fahum laa yafqahoon
That is because they believed, then denied — so their hearts were sealed, and they no longer understand.