وَقَوْمَ نُوحٍ مِّن قَبْلُ ۖ إِنَّهُمْ كَانُوا۟ قَوْمًا فَـٰسِقِينَ Qur’an Az-Zariyat (51:46)Waqawma noo h in min qablu innahum k a noo qawman f a siqeen a
The generation of Noah was swept away in the Flood for their sins: vii. 59-64. The point is that such a Flood seemed so unlikely to them that they thought Noah was "wandering in his mind" when he delivered Allah's Message: vii. 60.