Messenger of Allah ﷺ's said, "If a man and a woman agree (to marry temporarily), their marriage should last for three nights, and if they like to continue, they can do so; and if they want to separate, they can do so." I do not know whether that was only for us or for all the people in general. Abu ʿAbdullah (Al-Bukhari) said: ʿAli made it clear that the Prophet said, "The Mut'a marriage has been cancelled (made unlawful).
عَنْ رَسُولِ اللَّهِ ﷺ أَيُّمَا رَجُلٍ وَامْرَأَةٍ تَوَافَقَا فَعِشْرَةُ مَا بَيْنَهُمَا ثَلاَثُ لَيَالٍ فَإِنْ أَحَبَّا أَنْ يَتَزَايَدَا أَوْ يَتَتَارَكَا تَتَارَكَا فَمَا أَدْرِي أَشَىْءٌ كَانَ لَنَا خَاصَّةً أَمْ لِلنَّاسِ عَامَّةً قَالَ أَبُو عَبْدِ اللَّهِ وَبَيَّنَهُ عَلِيٌّ عَنِ النَّبِيِّ ﷺ أَنَّهُ مَنْسُوخٌ