DS2 was just coming to the end of his lunch break, his class are self-isolating, when DH came home. When he joined the class again, I told DH that he was in online classes now until 3. Immediately after that I heard him having a full blown conversation with DS2 when he was supposed to be watching a video. After he left DS2's room I reminded him again that he was in online classes until 3. He said, "Sorry, I forgot." How do I deal with this? DS2 is self-isolating until Monday.