Indeed, those who disbelieve - 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
إِنَّ ٱلَّذِينَ كَفَرُوا۟ سَوَآءٌ عَلَيْهِمْ ءَأَنذَرْتَهُمْ أَمْ لَمْ تُنذِرْهُمْ لَا يُؤْمِنُونَIndeed, those who disbelieve - it is all the same for them whether you warn them or do not warn them - they will not believe.