Hi there!
Thanks for conatcting us. Our Helix3, Helix ultimate framework and SP Page Builder are compatible with PHP 8.0 maximum. We are working to bring higher PHP support soon. Here is the plan:
https://www.joomshaper.com/blog/latest-php-compatibility-for-templates-and-extensions
The Declacroy template is based on the Helix Ultimate framework, but in some contexts it still arise some issues. No worries, as I said we are working to ensure higher PHP support for all of our products as well.
Best Regards