And it is all the same for them whether you warn them or do not warn them - they will not believe.
The Saheeh International Quran Translation
وَسَوَآءٌ عَلَيْهِمْ ءَأَنذَرْتَهُمْ أَمْ لَمْ تُنذِرْهُمْ لَا يُؤْمِنُونَAnd it is all the same for them whether you warn them or do not warn them - they will not believe.