BooleanField to checkboxinput in django won't work as it should

I have the following model that has a Boolean field among others

class Prb(models.Model):
    #other fields
    disabled = models.BooleanField(default=False)

and a modelform for the model

class PrbModelForm(ModelForm):

    class Meta:
        model=Prb

In my view I render prbmodelform with a prb as instance

prb = get_object_or_404(Prb, pk=4)
prb_model_form = PrbModelForm(request.POST or None, instance=prb)

prb.disabled field for this model is 0 (using SQLite database) but when I render the form although disabled field is 0 checkbox is checked. How can I solve this problem? I want to add here that disabled is an SQLite Boolean field, and that the data schema was transformed in to models using inspectdb. Why doesn't it render the checkbox status correctly?