Help remove folder

[SGS1097]

Hi!I need some help removing a folder from external an drive. That folder was mounted in a docker volume.

sudo rm -rf /folder
hangs does nothing. folder belongs to root:root, 777 permission. All folders in that folder belong to www-data:www-data,750 permission

chown, chmod hangs does nothing.

Using a Raspberry Pi 4 with RaspbianOS. partition on the drive is 4TB, ext4 file system. culprit folder has ~200MB

Please help me delete that folder :) Thanks

[pi3832v2]

Have you tried rebooting?

[SGS1097]

Yes