Override save method to also save the localised fields.

def save(self, commit=True):
        """
        Override save method to also save the localised fields.
        """
        # set the localised fields
        for localized_field in self.instance.localized_fields:
            setattr(self.instance, localized_field, self.cleaned_data[localized_field])

        return super(LocalisedForm, self).save(commit)