Allah Almighty sent revelation to His Messenger ﷺ in succession before his death, more abundantly than ever before, until Allah took his soul. Then he ﷺ passed away.
أن الله تعالى تابع على رسوله ﷺ قبل وفاته حتى توفاه الله أكثر ما كان الوحي، ثم توفي ﷺ.
Bukhari narrated it in the Virtues of the Quran (4982) and Muslim in the beginning of the Tafsir (3016), both from Amr bin Muhammad Naqid, who said, our teacher Yaqub bin Ibrahim narrated to us, my father narrated to me, from Salih bin Kaysan, from Ibn Shihab, who said, Anas bin Malik informed me, and he related it. The wording given is Bukhari's. In Muslim's wording it reads, "and the revelation was most frequent on the day the Messenger of Allah ﷺ passed away," meaning the period of his passing, not the specific day of his death.