Imran b. Husain (Allah be pleased with them) reported that the Messenger of Allah (ﷺ) said to him (or he said to another person and he was listening to it):O, so and so, did you observe fast in the middle of the month? He said: No. Thereupon he (the Messenger of Allah) said: When you break it, then observe fast for two days

English translation · Sahih Muslim