A man repeatedly brought for drinking was cursed by someone present: “May Allah curse him, how often he is brought!” The Prophet ﷺ said: “Do not curse him, for by Allah he loves Allah and His Messenger.” (al-Bukhārī). And: “Do not be helpers of Shayṭān against your brother.” (al-Bukhārī).
العربية: عن عمر رضي الله عنه أنّ رجلًا كان يُؤتى به إلى النبيّ ﷺ في الشراب، فقال رجل: لعنه الله ما أكثر ما يُؤتى به! فقال النبيّ ﷺ: «لا تلعنوه، فوالله ما علمتُ إلا أنه يحبّ الله ورسوله». (البخاري).
When someone falls into sin, don't curse them — make duʿā for their guidance and help them toward good.