Answered by Shaykh Faraz Rabbani
If I make up my makeup fast and break it? What is hukm on breaking it?
Walaikum assalam,
It is unlawful (haram) to break an obligatory fast, without any legal excuse that allows you to break the fast, as mentioned in the fiqh of fasting. This applies to makeup fasts as well.
(Answering someone’s invitation for food, for example, is not an excuse.)
Wassalam,
Faraz.