Cannot delete longhorn namespace

Hi all,
I have a k8s cluster internal setup by k3s.
I have installed longhorn by helm
helm install longhorn longhorn/longhorn --namespace longhorn -f values.yaml
Then I uninstall longhorn a few seconds later
helm -n longhorn uninstall longhorn
But something went wrong, I CTL+C, but then longhorn cannot be found with helm

helm -n longhorn list
NAME    NAMESPACE       REVISION        UPDATED STATUS  CHART   APP VERSION

However, the longhorn namespace is still there and I want to delete this namespace.
kubectl delete ns longhorn --grace-period=0 --force --cascade=true
hang for long time

kubectl get ns
NAME                STATUS        AGE
longhorn            Terminating   70m

kubectl api-resources --verbs=list --namespaced -o name | xargs -n 1 kubectl get --ignore-not-found --show-kind -n longhorn
NAME                                  STATE      IMAGE                               REFCOUNT   BUILDDATE   AGE
engineimage.longhorn.io/ei-68f17757   deployed   longhornio/longhorn-engine:v1.5.3   0          25d         62m
NAME                              READY   ALLOWSCHEDULING   SCHEDULABLE   AGE
node.longhorn.io/k3s-hq-master1   True    true              True          62m
NAME                                                                                  VALUE                                         AGE
setting.longhorn.io/crd-api-version                                                   longhorn.io/v1beta2                           62m
setting.longhorn.io/current-longhorn-version                                          v1.5.3                                        62m
setting.longhorn.io/backup-target                                                                                                   62m
setting.longhorn.io/default-backing-image-manager-image                               longhornio/backing-image-manager:v1.5.3       62m
setting.longhorn.io/support-bundle-manager-image                                      longhornio/support-bundle-kit:v0.0.27         62m
setting.longhorn.io/backup-target-credential-secret                                                                                 62m
setting.longhorn.io/default-engine-image                                              longhornio/longhorn-engine:v1.5.3             62m
setting.longhorn.io/allow-recurring-job-while-volume-detached                         false                                         62m
setting.longhorn.io/default-instance-manager-image                                    longhornio/longhorn-instance-manager:v1.5.3   62m
setting.longhorn.io/create-default-disk-labeled-nodes                                 false                                         62m
setting.longhorn.io/default-data-path                                                 /var/lib/longhorn/                            62m
setting.longhorn.io/replica-soft-anti-affinity                                        false                                         62m
setting.longhorn.io/replica-auto-balance                                              disabled                                      62m
setting.longhorn.io/storage-over-provisioning-percentage                              100                                           62m
setting.longhorn.io/storage-minimal-available-percentage                              25                                            62m
setting.longhorn.io/storage-reserved-percentage-for-default-disk                      30                                            62m
setting.longhorn.io/upgrade-checker                                                   true                                          62m
setting.longhorn.io/allow-collecting-longhorn-usage-metrics                           true                                          62m
setting.longhorn.io/latest-longhorn-version                                                                                         62m
setting.longhorn.io/stable-longhorn-versions                                                                                        62m
setting.longhorn.io/default-replica-count                                             3                                             62m
setting.longhorn.io/default-data-locality                                             disabled                                      62m
setting.longhorn.io/default-longhorn-static-storage-class                             longhorn-static                               62m
setting.longhorn.io/backupstore-poll-interval                                         300                                           62m
setting.longhorn.io/taint-toleration                                                                                                62m
setting.longhorn.io/system-managed-components-node-selector                                                                         62m
setting.longhorn.io/auto-salvage                                                      true                                          62m
setting.longhorn.io/auto-delete-pod-when-volume-detached-unexpectedly                 true                                          62m
setting.longhorn.io/registry-secret                                                                                                 62m
setting.longhorn.io/disable-scheduling-on-cordoned-node                               true                                          62m
setting.longhorn.io/replica-zone-soft-anti-affinity                                   true                                          62m
setting.longhorn.io/node-down-pod-deletion-policy                                     do-nothing                                    62m
setting.longhorn.io/node-drain-policy                                                 block-if-contains-last-replica                62m
setting.longhorn.io/priority-class                                                                                                  62m
setting.longhorn.io/disable-revision-counter                                          false                                         62m
setting.longhorn.io/replica-replenishment-wait-interval                               600                                           62m
setting.longhorn.io/concurrent-replica-rebuild-per-node-limit                         5                                             62m
setting.longhorn.io/concurrent-volume-backup-restore-per-node-limit                   5                                             62m
setting.longhorn.io/system-managed-pods-image-pull-policy                             if-not-present                                62m
setting.longhorn.io/allow-volume-creation-with-degraded-availability                  true                                          62m
setting.longhorn.io/auto-cleanup-system-generated-snapshot                            true                                          62m
setting.longhorn.io/concurrent-automatic-engine-upgrade-per-node-limit                0                                             62m
setting.longhorn.io/backing-image-cleanup-wait-interval                               60                                            62m
setting.longhorn.io/backing-image-recovery-wait-interval                              300                                           62m
setting.longhorn.io/guaranteed-instance-manager-cpu                                   12                                            62m
setting.longhorn.io/kubernetes-cluster-autoscaler-enabled                             false                                         62m
setting.longhorn.io/orphan-auto-deletion                                              false                                         62m
setting.longhorn.io/storage-network                                                                                                 62m
setting.longhorn.io/failed-backup-ttl                                                 1440                                          62m
setting.longhorn.io/recurring-successful-jobs-history-limit                           1                                             62m
setting.longhorn.io/recurring-failed-jobs-history-limit                               1                                             62m
setting.longhorn.io/support-bundle-failed-history-limit                               1                                             62m
setting.longhorn.io/deleting-confirmation-flag                                        false                                         62m
setting.longhorn.io/engine-replica-timeout                                            8                                             62m
setting.longhorn.io/snapshot-data-integrity                                           fast-check                                    62m
setting.longhorn.io/snapshot-data-integrity-cronjob                                   0 0 */7 * *                                   62m
setting.longhorn.io/snapshot-data-integrity-immediate-check-after-snapshot-creation   false                                         62m
setting.longhorn.io/restore-volume-recurring-jobs                                     false                                         62m
setting.longhorn.io/remove-snapshots-during-filesystem-trim                           false                                         62m
setting.longhorn.io/fast-replica-rebuild-enabled                                      true                                          62m
setting.longhorn.io/replica-file-sync-http-client-timeout                             30                                            62m
setting.longhorn.io/backup-compression-method                                         lz4                                           62m
setting.longhorn.io/backup-concurrent-limit                                           2                                             62m
setting.longhorn.io/restore-concurrent-limit                                          2                                             62m
setting.longhorn.io/log-level                                                         Info                                          62m
setting.longhorn.io/v2-data-engine                                                    false                                         62m
setting.longhorn.io/v2-data-engine-hugepage-limit                                     1024                                          62m
setting.longhorn.io/offline-replica-rebuilding                                        enabled                                       62m
Warning: metallb.io v1beta1 AddressPool is deprecated, consider using IPAddressPool

Please give me some advice, thank you very much.

I found solution here : Longhorn Namespace Stuck Terminating - Delete Longhorn from Kubernetes Cluster
Patch all the CRDs and delete the finalizers. This can be done with this command: for crd in $(kubectl get crd -o name | grep longhorn); do kubectl patch $crd -p '{"metadata":{"finalizers":[]}}' --type=merge; done;

Before you uninstall Longhorn, you should set the setting deleting-confirmation-flag to true.
If you delete the namespace directly, there might be some CRs that will never be deleted because the webhook server is deleted.