With the help of Bubble Support I think I found it- somehow I had a “if the user is logged out go to index page” workflow - to my horror in the FOOTER!
Ok so I have removed that now- any suggestions on how best to approach an attempt to re-index?
It’s likely that Google never truly de-indexed it, rather just sort of hid it when they spotted the problem and checked back periodically to see if the issue resolved. Once it saw it had, it just unhid back at its previous spot.
Just wanted to add in some extra info for anyone out there experiencing a “de-index” from Google without any site errors causing it. I just spent some time trying to figure out why a Bubble app that was showing up on 1st page results for the app name had suddenly disappeared. The only changes made were content - a lot of new content, some new pages, some removed pages, etc. Overall, no weird workflows or re-directs. In fact, after doing the same crawl in the Google Search Console (where OP got redirection errors), this app returned a successful response.
A simple request for re-indexing completely restored it. Literally within 5 minutes, it was showing up again in Google. The app isn’t that heavy, so for other apps with more going on, it might take longer (up to 24 hrs).
It was a bit of a panic for app owner, and I’m also learning more and more about SEO. I came across some common suggestions, and the following in some SEO blog summed it up nicely:
As time goes on and you add new features or content to the site, Google’s site crawlers will recognize that the site is an active one, and crawl the site more regularly. Submitting your site for re-indexing will become unnecessary once this happens.