[Machine] Whoever breaks (fast) one day of Ramadan without justification, their fasting for the rest of their life will not be accepted until they meet Allah. If He wishes, He will forgive them, and if He wishes, He will punish them. Another narration from Ibn Mas'ood mentions (the same).
مَنْ أَفْطَرَ يَوْمًا مِنْ رَمَضَانَ مِنْ غَيْرِ عِلَّةٍ لَمْ يُجْزِهِ صِيَامُ الدَّهْرِ حَتَّى يَلْقَى اللهَ ﷻ فَإِنْ شَاءَ غَفَرَ لَهُ وَإِنْ شَاءَ عَذَّبَهُ وَرُوِيَ مِنْ وَجْهٍ آخَرَ عَنِ ابْنِ مَسْعُودٍ