Uninstall a manually added theme
In case if your theme was created or installed manually, the uninstall procedure is the same, regardless the way Magento was installed.
To uninstall a manually added theme:
- Navigate to the vendor directory where the theme was installed. This directory should be:
<Magento root dir>/app/design/frontend/<VendorName>.
- Remove the theme directory.
- Remove the theme record from database. If you are using MySQL, run the following command to do this:
mysql -u <user> -p -e "delete from <dbname>.theme where theme_path ='<Vendor>/<theme>' AND area ='frontend' limit 1"
- <user>: your Magento database user name
- <dbname>: your Magento database name
- <Vendor>/<theme>: relative path to the theme directory
Source: Magento Devdocs