The Prophet ﷺ said about the woman having a prolonged flow of blood: She should abandon prayer during her menstrual period: then she should take a bath and pray. She should perform ablution for every prayer. Abu Dawud said: 'Uthman added: She should keep fast and pray.
عَنِ النَّبِيِّ ﷺ فِي الْمُسْتَحَاضَةِ تَدَعُ الصَّلاَةَ أَيَّامَ أَقْرَائِهَا ثُمَّ تَغْتَسِلُ وَتُصَلِّي وَالْوُضُوءُ عِنْدَ كُلِّ صَلاَةٍ