Soft 404 error | out from index

Hello.
I’m facing something incomprehensible. At one point google stopped loading the application pages for indexing. It marked index page as soft 404, and in the live test it shows black text on white background “Your browser unable to load the applocation data”.
The home page of the app, and a great many just left the search engine. Maybe someone knows what this is and how to fix it?

Me And my friend on other project facing the same

bubble support rejected to investigate and help. but this is definetely bubble engine
I have light weight index and before it was indexing normally

for those who struggle wit this problem

set your robots.txt to default values
hide sitemap
deploy
verify your domain in search console
when passed you can return your settings