4:137
إِنَّ ٱلَّذِينَ ءَامَنُوا۟ ثُمَّ كَفَرُوا۟ ثُمَّ ءَامَنُوا۟ ثُمَّ كَفَرُوا۟ ثُمَّ ٱزْدَادُوا۟ كُفْرًا لَّمْ يَكُنِ ٱللَّهُ لِيَغْفِرَ لَهُمْ وَلَا لِيَهْدِيَهُمْ سَبِيلًۢا
inna alladhīna āmanū thumma kafarū thumma āmanū thumma kafarū thumma iz'dādū kuf'ran lam yakuni l-lahu liyaghfira lahum walā liyahdiyahum sabīlan
As for those who believe, then reject the faith, then believe again, then reject the faith again and become increasingly defiant, God will not forgive them, nor will He guide them on any path.
Verily, those who believe, then disbelieve, then believe (again), and (again) disbelieve, and go on increasing in disbelief; Allâh will not forgive them, nor guide them on the (Right) Way.