ownCloud on Ubuntu 20.04

Hi everyone I’m doing an Owncloud installation on Ubuntu 20.04, following the guide https://doc.owncloud.com/server/10.7/admin_manual/installation/quick_guides/ubuntu_20_04.html#download-owncloud at the time of Owncloud installation by running the command “occ maintenance …” I get “Command” $ @ “is not defined.” can you help me? Thank you