The Prophet ﷺ said: When a man makes a promise to his brother with the intention of fulfilling it and does not do so, and does not come at the appointed time, he is guilty of no sin.
عَنِ النَّبِيِّ ﷺ قَالَ إِذَا وَعَدَ الرَّجُلُ أَخَاهُ وَمِنْ نِيَّتِهِ أَنْ يَفِيَ لَهُ فَلَمْ يَفِ وَلَمْ يَجِئْ لِلْمِيعَادِ فَلاَ إِثْمَ عَلَيْهِ