question #1 Sahih al-Bukhari 1959, Book 30, Hadith 66 : What should be done if a fast is broken due to a mistake, such as breaking it on a cloudy day when the sun is still up?

Asma bint Abi Bakr said, “We broke our fast during the lifetime of the Prophet (ﷺ) on a cloudy day and
then the sun appeared.” Hisham was asked, “Were they ordered to fast in lieu of that day?” He replied,
“It had to be made up for.” Ma`mar said, “I heard Hisham saying, “I don’t know whether they fasted in
lieu of that day or not.”