ENOfficial
Abu Umama reported God’s Messenger as saying, “If anyone hoards grain for forty days and then gives it in sadaqa, that will not act as an atonement for him.” Razin transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَنْ أَبِي أُمَامَةَ: أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «مَنِ احْتَكَرَ طَعَامًا أَرْبَعِينَ يَوْمًا ثمَّ تَصَدَّقَ بِهِ لَمْ يَكُنْ لَهُ كَفَّارَةً» . رَوَاهُ رزين
sunnah.com