Removing symlink is not working

I am trying to install sample data using Github repo: https://github.com/magento/magento2-sample-data#deploy-sample-data-from-github-repository

First I ran the following command to symlink:
`php -f /path/to/my/sample-data/dev/tools/build-sample-data.php -- --ce-source="/path/to/my/magento2"`
And got success message as:

> All symlinks you can see at files:
> /path/to/my/sample-data/dev/tools/exclude.log

Now when I tried to install Magento 2 from cli, it got stuck saying

> Class Magento\Catalog\Model\ResourceModel\Product\Gallery does not exist

So I thought of removing the symlinks and ran:
`php -f /path/to/my/sample-data/dev/tools/build-sample-data.php – --command=unlink --ce-source="/path/to/my/magento2"`
but resulted in error

> Expected folder not found

Any idea about the issue?
How to install sample data from github?

Start with dev/tools/build-sample-data.php and compare the documented symlink command with the unlink command shown in the report, including the command-line separator and --ce-source path. Check the generated dev/tools/exclude.log and the reported “Expected folder not found” error. Done means the unlink command handles the reported setup and the sample-data installation path is documented clearly.

Written by the indexing model from the issue text.