مَن كَذَبَ عَلَيَّ مُتَعَمِّدًا، فَلْيَتَبَوَّأْ مَقْعَدَهُ مِنَ النَّارِ
[The Prophet ﷺ said]: Whoever lies upon me intentionally, then let him take his seat in the Hellfire.
Notice how such a crucial statement, that is absolutely necessary to ensure authenticity is massly transmitted. Which believer would dare lie upon the Prophet ﷺ after hearing something like this?
سأل أهل مكة النبي - صلى الله عليه وسلم - آية ، فانشق القمر بمكة مرتين
The people of Makkah asked the Prophet ﷺ for a sign, so the moon split in Makkah twice.
This same incident is mentioned in multiple narrations from numerous companions of the Prophet ﷺ, as is mentioned by the medieval scholar Ibn Kathir in his exegesis of the Great Qur'aan. Glory be to Allaah. Is this not enough evidence?
It is good to know that this is merely one out of the numerous miracles recorded by means of mass transmission.