Pimcore 5 Migration - pimcore5:migrate:filesystem

I am trying to execute this command
pimcore.phar pimcore5:migrate:filesystem pimcore-unstable.zip
as mentioned here https://github.com/pimcore/pimcore-cli/blob/master/doc/pimcore_5_migration.md

However, I am getting an error "Not enough arguments (missing: “zipFile”).

I am using pimcore.phar version 1.3.3

The pimcore-unstable.zip is located in the web root directory.

Need Help !