Container Block doesn’t work anymore

Hello,

I use Stackable – Gutenberg Blocks on my website.
Now the Container Block does not seem to work anymore.
Since yesterday the following error message appears: Your website does not support the .ugb/container block.
Because of that the layout of my Website is off.

Does anyone know the reason, why it doesn’t work anymore. In the inserter tool, the container block can’t be found either.
However, the plugin is still activated and updated.
Ist the container Block no longer avaiable in the free version?
Is there a simple way to fix this?

Best regards