What is the reason why the teacher deliberately doesn't reply to the information sent by his parents?

Teacher, what is the reason for seeing parents send messages and deliberately not returning them? I think this parent has some opinions about this teacher and this student, so he didn't tell his parents the news. This teacher has no respect for the parents of students, as do many responsible teachers in reality. We think such teachers should leave. Teachers who don't contact their parents in the future won't recognize everyone because they don't have the right attitude and thinking, so I think such teachers should leave the podium and don't waste the time of students and parents here.