Cannot build my first block

Hi all,

I’m trying to build my first block with this tutorial, and installed wp-env and @wordpress/scripts etc. based on previous introduction. However, the first block “copyright-date-block” cannot be shown in my new post/page and I cannot find any introduction about this problem.

My steps are:

1. Create a block plugin by command:

npx @wordpress/create-block@latest copyright-date-block –variant=dynamic

2. Enter copyright-date-block and start wp-env:

wp-env start

3. Visit http://localhost:8888, login, and make sure the copyright date block plugin is activated.
4. Click “New” to the page for creating a new post/page, Click the add icon to open the blocks, search “copy”, it should exist based on the tutorial but it doesn’t.

Other information may help:

1. In web dev tools, there is only css being loaded. 
2. block.json and index.js is able to be visited in url. So it is deployed to the server.
3. Not use wp-env, but copy the build folder and copyright-date-block.php to another wordpress environment, the problem still exists.

Code was uploaded to this github repository.

Thanks for any suggestions.

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