Error - There is no data to update.

The error still occurs

PHP Code:

$this->data['request'] = $this->request;
        $data = [
            'einh_art_id' => $this->request->getPost('einh_art_id'),
            'einh_qm' => $this->request->getPost('einh_qm'),
            'einh_zimmer' => $this->request->getPost('einh_zimmer'),
            'einh_kueche' => $this->request->getPost('einh_kueche'),
            'einh_bad' => $this->request->getPost('einh_bad'),
            'einh_ebk' => $this->request->getPost('einh_ebk'),
            'einh_badewanne' => $this->request->getPost('einh_badewanne'),
            'einh_dusche' => $this->request->getPost('einh_dusche'),
            'einh_balkon' => $this->request->getPost('einh_balkon')
        ];
        if(!empty($this->request->getPost('einh_id')))
        {
            $einh_id = $this->request->getPost('einh_id');
            $this->EinheitenModel->update($einh_id, $data);
        }