"The inscription on the ring of the Prophet ﷺ was in three line: 'Muhammad' on a line, 'Messenger' on a line, 'Allah' on a line." And Muhammad bin Yahya (one of the two who narrated to him) did not say: "Three lines" in his narration. There are narrations on this topic from Ibn 'Umar.
كَانَ نَقْشُ خَاتَمِ النَّبِيِّ ﷺ ثَلاَثَةَ أَسْطُرٍ مُحَمَّدٌ سَطْرٌ وَرَسُولُ سَطْرٌ وَاللَّهِ سَطْرٌ وَلَمْ يَذْكُرْ مُحَمَّدُ بْنُ يَحْيَى فِي حَدِيثِهِ ثَلاَثَةَ أَسْطُرٍ وَفِي الْبَابِ عَنِ ابْنِ عُمَرَ
that when Abu Bakr became the Caliph, he wrote a letter to him (and stamped it with the Prophet's ring) and the engraving of the ring was in three lines: Muhammad in one line, 'Apostle' in another line, and 'Allah' in a third line.
أَنَّ أَبَا بَكْرٍ ؓ لَمَّا اسْتُخْلِفَ كَتَبَ لَهُ وَكَانَ نَقْشُ الْخَاتَمِ ثَلاَثَةَ أَسْطُرٍ مُحَمَّدٌ سَطْرٌ وَرَسُولُ سَطْرٌ وَاللَّهِ سَطْرٌ
"The inscription on the ring of the Prophet ﷺ was in three lines: 'Muhammad' on a line, 'Messenger' on a line, and 'Allah' on a line." (Using translation from Tirmidhī 1747)
«كَانَ نَقْشُ خَاتَمِ النَّبِيِّ ﷺ ثَلَاثَةَ أَسْطُرٍ مُحَمَّدٌ سَطْرٌ وَرَسُولُ سَطْرٌ وَاللَّهِ سَطْرٌ»
"The inscription on the ring of the Prophet ﷺ was in three lines: 'Muhammad' on a line, 'Messenger' on a line, and 'Allah' on a line." (Using translation from Tirmidhī 1747)
كَانَ «نَقْشُ خَاتَمِ النَّبِيِّ ﷺ ثَلَاثَةَ أَسْطُرٍ مُحَمَّدٌ سَطْرٌ وَرَسُولٌ سَطْرٌ وَاللَّهُ سَطْرٌ»
"The inscription on the ring of the Prophet ﷺ was in three lines: 'Muhammad' on a line, 'Messenger' on a line, and 'Allah' on a line." (Using translation from Tirmidhī 1747)
«كَانَ نَقْشُ خَاتَمِ النَّبِيِّ ﷺ ثَلَاثَةَ أَسْطُرٍ مُحَمَّدٌ سَطْرٌ وَرَسُولٌ سَطْرٌ وَاللَّهُ سَطْرٌ»