Reusable Section Error with colibri

Hello all ??
I’m trying to create a reusable block for my site, but colibri fails with error “Could not save reusable section”.
Inspecting I have errors of 404 not found ( see link ), seems some files are missing from theme. I tryed to reinstall colibri-wp theme, disable all other plugins but error still pop-up.

Can someone help me with this issue? Where I can find the missing files?

Screenshot of console error

The page I need help with: [log in to see the link]