Divine justice and the principle that forgiveness requires sincere repentance

ٱسْتَغْفِرْ لَهُمْ أَوْ لَا تَسْتَغْفِرْ لَهُمْ إِن تَسْتَغْفِرْ لَهُمْ سَبْعِينَ مَرَّةً فَلَن يَغْفِرَ ٱللَّهُ لَهُمْ ۚ ذَٰلِكَ بِأَنَّهُمْ كَفَرُوا۟ بِٱللَّهِ وَرَسُولِهِۦ ۗ وَٱللَّهُ لَا يَهْدِى ٱلْقَوْمَ ٱلْفَـٰسِقِينَ

Ask forgiveness for them, [O Muḥammad], or do not ask forgiveness for them. If you should ask forgiveness for them seventy times - never will Allāh forgive them. That is because they disbelieved in Allāh and His Messenger, and Allāh does not guide the defiantly disobedient people.