School incident?

So my son (8) is supposed to go to after school program. He told his teacher he didn’t want to go today. She said she’s needs my number to call & let me know. I’m confused about that because she has my number. We’ve text on many occasions & we’ve also communicated on the parent/teacher app. Then my son asked to go to the office, she sent him but they were on lunch break. When he got back to class he went up to his teachers desk & asked “can I give you my mom’s number now because I still don’t want to go to after school?” The teacher replies “no, go sit down.” At the end of the day my son goes to the office & asked them to call me someone told him “I don’t have to call your mom your teacher should have done that.” Basically my son got on the bus to come home & no one was at the bus stop. He stayed on the bus until about 4:30 while the bus driver did other stops. When his dad went to pick him up from after school the principal told him my son just got back to the school & that he was on the bus that whole time. I know he was wrong for getting on the bus knowing he was supposed to stay at school. I also feel like his teacher & office is wrong for not texting or calling me and allowing him to leave. Should I go to the school tomorrow? Call his teacher or the office?
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2 mo
It’s supposed to be an 8 where the heart eyes are.
School incident?
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