Laravel soft deleting with related table

Hi,

I'd like to delete entities and related tables.

I tried with event :

/**
     * Handle the DossierFinancingPlanModel "deleting" event.
     */
    public function deleting(DossierFinancingPlanModel $dossierFinancingPlanModel): void
    {
        $dossierFinancingPlanModel->dossierFinancingPlanCalculated()->delete();
        $dossierFinancingPlanModel->dossierFinancingPlanCharges()->delete();
        $dossierFinancingPlanModel->dossierFinancingPlanDebts()->delete();
        $dossierFinancingPlanModel->dossierFinancingPlanLoans()->delete();
        $dossierFinancingPlanModel->dossierFinancingPlanNeeds()->delete();
        $dossierFinancingPlanModel->dossierFinancingPlanProperties()->delete();
        $dossierFinancingPlanModel->dossierFinancingPlanResources()->delete();
    }

But a I this error :

SQLSTATE[23000]: Integrity constraint violation: 1451 Cannot delete or update a parent row: a foreign key constraint fails (`hub.wineo.io`.`dossier_financing_plan_calculated`, CONSTRAINT `dfpca_dfp_id` FOREIGN KEY (`dossier_financing_plan_id`) REFERENCES `dossier_financing_plan` (`id`)) (Connection: mysql, SQL: delete from `dossier_financing_plan` where `id` = 5f92b813-a32e-484e-a3f3-ee57990b1e52)

I don't understand why, "deleting" event means "DossierFinancingPlanModel" not deleted yet ?!