Narrated Anas ibn Malik: When the Prophet (ﷺ) entered the privy, he removed his ring. Abu Dawud said: This is a munkar tradition, i.e. it contradicts the well-known version reported by reliable narrators. On the authority of Anas the well-known version says: The Prophet (ﷺ) had a silver ring made for him. Then he cast it off. The misunderstanding is on the part of Hammam (who is the narrator of the previous tradition mentioned in the text). This is transmitted only by Hammam.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا نَصْرُ بْنُ عَلِيٍّ، عَنْ أَبِي عَلِيٍّ الْحَنَفِيِّ، عَنْ هَمَّامٍ، عَنِ ابْنِ جُرَيْجٍ، عَنِ الزُّهْرِيِّ، عَنْ أَنَسٍ، قَالَ كَانَ النَّبِيُّ صلى الله عليه وسلم إِذَا دَخَلَ الْخَلاَءَ وَضَعَ خَاتَمَهُ . قَالَ أَبُو دَاوُدَ هَذَا حَدِيثٌ مُنْكَرٌ وَإِنَّمَا يُعْرَفُ عَنِ ابْنِ جُرَيْجٍ عَنْ زِيَادِ بْنِ سَعْدٍ عَنِ الزُّهْرِيِّ عَنْ أَنَسٍ أَنَّ النَّبِيَّ صلى الله عليه وسلم اتَّخَذَ خَاتَمًا مِنْ وَرِقٍ ثُمَّ أَلْقَاهُ . وَالْوَهَمُ فِيهِ مِنْ هَمَّامٍ وَلَمْ يَرْوِهِ إِلاَّ هَمَّامٌ .
sunnah.com