If your daughter is failing her classes, then perhaps she has a problem, either physical or psychological, that needs to be addressed. When was the last time your daughter saw her doctor, or had her vision and hearing checked? Has she ever been evaluated for intellectual disabilities, or possibly for Autism? Is she getting bullied in school? Are there other issues going on, such as a personality conflict with a teacher or school officials? You need to find the answers to these questions, because there may be a good reason why things aren't going right.
One thing I would do is tone down the nagging about grades. Nobody, and I don't give a rat's behind who they are, appreciates being nagged constantly about something that is giving them problems. Nagging is like fat shaming someone who is over weight. Most of the time, the person is WELL AWARE that they have a problem, and they DON'T NEED to be constantly reminded of it, often by people who are totally IGNORANT about the circumstances of the situation. There are any number of reasons why your daughter could be unable to do her schoolwork, and not all of them are under her( or your) control. What you need to do is make more of an effort to learn what is really behind your daughter's situation, not make it worse by constantly nagging at her.
I get that you want your daughter to have a good education, and that education is important to you. My parents felt the same way when I was young. But you're not going to improve things by being constantly on her case, especially when you won't do anything to help her besides complain that she's not working hard enough. Maybe the reason she isn't doing her work is because she feels that she can't.