Question: The one who left off fasting deliberately without an excuse, but due to work in the years that have past, is it upon him to make it up?
Answer: “Making up the fast is only for the one who left it off for an excuse. This excuse is like travelling, sickness, menstruation, and post-natal bleeding. As for the one who left it off deliberately, then there is nothing upon him except repentance to Allah, the Exalted”
[al-‘Athab al-Ma’een pg. 53]
Faisal Ibn Abdul Qaadir Ibn Hassan