Sunan an-Nasa'i 910
سنن النسائي#910SahihIt was narrated from Ubadah bin As-Samit that :The Prophet (ﷺ) said: "There is no Salah for one who does not recite Fatihatil-Kitab
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 11:35