Victor12 It's obviously not a cache problem.
It could very well be one.
What extension did you install?
Did you use Reflar Uncache or run the following in your Flarum root folder:
php flarum cache:clear
rm assets/rev-manifest.json
Clear your Cloudflare cache if applicable.
Then hard refresh (CTRL+F5) your browser?
If you did all that to clear the cache, then it's possible the extension you installed is not working with Beta 7.x. You can remove it with composer remove vendor/packagename where vendor/packagename is unique to your extension (like flarum/flarum-ext-english).
