How do you delete a dataset created by cloning a snapshot?

After quite some searching and reading, i still cannot figure out how to get rid of a a dataset created by cloning a snapshot. The dataset is located at /mnt/Jails/iocage/jails-auto-20200525.1523-3m-clone and so far tried:

• Checked dataset contents: ls -all --> empty (just “.” and “..”)
• Delete (shell, root): rmdir jails-auto-20200525.1523-3m-clone --> Device busy
• Unmount: zfs unmount -f jails-auto-20200525.1523-3m-clone --> dataset does not exist
• Delete connected...

How do you delete a dataset created by cloning a snapshot?