The Prophet ﷺ said about a person who had intercourse with his wife while she was menstruating: He must give one dinar or half a dinar in alms. Abu Dawud said: The correct version says si: One dinar or half a dinar. Shu'bah (a narrator) did not sometimes narrate this tradition as a statement of the Prophet ﷺ.
عَنِ النَّبِيِّ ﷺ فِي الَّذِي يَأْتِي امْرَأَتَهُ وَهِيَ حَائِضٌ قَالَ يَتَصَدَّقُ بِدِينَارٍ أَوْ نِصْفِ دِينَارٍ