﴿ وَحَرَٰمٌ عَلَىٰ قَرْيَةٍ أَهْلَكْنَٰهَآ أَنَّهُمْ لَا يَرْجِعُونَ ﴾

“Hence, it has been unfailingly true of any community whom We have ever destroyed that they [were people who] would never turn back [from their sinful ways]”

Please check ayah 21:97 for complete tafsir.