"D not fast until you see it , and do not stop fasting until you see it, and if it is obscured from you (too cloudy), then work it out." (Using translation from Nasāʾī 2122)

عَنِ النَّبِيِّ ﷺ قَالَ لَا تَصُومُوا حَتَّى تَرَوْا الْهِلَالَ وَلَا تُفْطِرُوا حَتَّى تَرَوْهُ فَإِنْ غُمَّ عَلَيْكُمْ فَاقْدُرُوا لَهُ