Is it obligatory to make up or offer expiation for someone who intended to do something that breaks the fast during Ramadan days due to ignorance or doubt, then their doubt increased and they refrained from it?

Whoever intends to do something that breaks the fast out of ignorance, then refrains from it for fear that it might invalidate the fast, does not have to make up for it. This is because merely intending to break the fast does not invalidate it, and because whoever does something that breaks the fast out of ignorance does not invalidate their fast by it, according to the soundest opinion. Sheikh al-Islam Ibn Taymiyyah said: "The most apparent opinion is that none of that needs to be made up." The Prophet, peace and blessings be upon him, pardoned the one who ate or drank intentionally during the day of fasting, not out of forgetfulness, because he misinterpreted the white and black thread.