if the black stone don't give benefits or harm then how come it whoever kiss get their sins forgived

In this hadith it says It is a stone that can neither bring about benefit nor cause harm, as ‘Umar Al-Farooq may Allah be pleased with him said, and it was proven in the two Saheehs [Al-Bukhari and Muslim]. but another hadith says "O Abu abdur-Rahman, why do I only see you touching these two corners?" He said: "I heard the Messenger of Allah say: 'Touching them erases sins.' And I head him say: 'whoever circumambulates seven times, it is like freeing a slave.'" Reference : Sunan an-Nasa'i 2919 In-book reference : Book 24, Hadith 302 English translation : Vol. 3, Book 24, Hadith 2922 I couldn't find the hadith reference for the first one, but im confused about as if the black stone dont give any benefits nor harm then how come it forgive sins and do other benefits?