try not to raise your voice or appear agitated. When she stands in the bathroom and not brushing teeth, you take a look and leave quietly.
Be more present when there is not any probelm, i.e., do not only appear when there is a problem. Break the connection between "problem" and attention from parents.
It seems that she lacks her own initiative and likes to be prodded.
Praise her more often for a job well done. Don't tell her that she has a problem, or make a lot of noise when seeking help.
Make sure that your own anxiety about the problem does not make it worse.
