PostCSS does nothing.

Yesterday, when PhpStorm was closed, everything worked fine, the project was going as it should. Now when I opened the project again and received the message:

You have not installed any plugins, parser or stringifier. PostCSS is not doing anything right now. Select plugins for your case at https://www.postcss.parts/ and use them in postcss.config.js.

I decided to revise the project, reinstalled all modules (using TailwindCss). I did everything as in the documentation, but I still get this message, while the project shows that it is fully assembled.

What other modules does he need, and why didn't I receive these messages yesterday?