My parents said I bothered them when forming a separate group to talk

First graders need the cooperation of their parents, and my work makes them uncomfortable.

I am a first-grade teacher, there are 38 children, the children are young, just moved from preschool, so I am very hard to manage and teach. At the beginning of the school year, my parents asked for my phone number and formed a group to inform parents about their children's learning. I also made it clear when the activity group was a teacher announcing their studies; The teacher said the content and the parents read it, if anyone does not understand anything then ask the teacher to answer, parents do not need to thank or message any personal things into the group.

The group has been active for two months and I have always been reminded and even criticized just because some parents are not aware that joining the group is a collective activity, whatever they say in spite of time and irrelevant content, there are parents who annoy them and frankly tell them what to put them into the group to receive spam messages all day. I was really shy, originally 38 members, now more than 15 people; Many announcements are needed, and the changing hours make me feel very pressured when managing a class like that. Hope you give me more ideas.