OP here. Thanks everyone. The bully us the girl. And I have spoken to the principal and they put some strategies in place to keep an eye on the kids but nothing stops that child from pushing (the principal talked to a child, parents were called, behavior plan etc). The bully just grew angrier and does not stop intimidating.

Is the bully a girl or a boy? A lot of girl bullies are great at sucking up to the teacher and carefully timing their bullying acts so no adults ever see them. It's an uphill battle to be taken seriously, since the administration is already dismissive about girl on girl bullying, and the bully is often the teacher's pet.

Demand your child be allowed to head to next class 5 min early. My kid has this.

Does your dd have anxiety or is she in therapy? The school needs to put a stop to it, and this is not her fault at all. But if she is feeling like she can't say "stop pushing" in a stern voice, that sounds like anxiety.

And who wouldn't have anxiety when stuck in an unsafe situation? I would push back with the school. It does not have to be seen to be bullying. Their primary focus should be your child feeling safe at school because kids can't learn when they are worried and threatened.