Codes on https://jupyter.org/try-jupyter/lab/ not working properly anymore

Yes, selecting from the ‘Pinned’ options near the top of that page, the requirements example or conda example, and then launching a binder instance using the launch binder badge will get you back to the more typical kernel activity you expect. The launch badge for both will spin up a JupyterLab interface and you can switch back to the classic notebook if you prefer by select from the menubar Help > Launch Classic Notebook.

There’s shortcuts to doing a lot of that if you find it more taxing than just when you would go to TryJupyter and click one of the tiles. For example, using the following URL, or this link, you can launch right into the classic notebook interface for the requirements example with the Jupyter dashboard presented at the start:

http://mybinder.org/v2/gh/binder-examples/requirements/master?urlpath=/tree/

Or with this link you can launch right into the classic notebook interface based on the requirements example with the index.ipynb notebook coming up the start & that URL is:

http://mybinder.org/v2/gh/binder-examples/requirements/master?urlpath=%2Fnotebooks%2Findex.ipynb

You can come back here and select those links or keep the URLs themselves handy.
If you change part of the URL that’s based on the repo name you can alternatively use the conda example as the basis, i.e, change requirements to conda in the URLs.