Hi Everett

First of all I am sorry for the late reply, I was vacationing the last 7 days.

Thank you for your reply. I think you might be right about the "sandbox" thing. The page had a good position in the google search results, but then we made a mistake and canonicalized it to a non-existent page for 4 months. It could be that google considers it a "new page", even though they had it indexed for a year.

I appreciate your efforts, and I will wait some time, to see if it improves by itself, otherwise I will have to work some more on improving the contents of the site.

Hi Ross

Thank you a lot for all the recommendations, I will get those things done and get back on here with the result.

Though currently I have the Yoast SEO plugin, and have generated a sitemap with only the pages we want ranking, which I did already upload to GSC, but I will make sure there is a link in the footer as well.

And also I did a 301 redirect on all these "attachment" pages, but I will change that to a 410.

Hello experts

I have a problem. The main page of my homepage got deranked severely and now I am not sure how to get the rank back.

It started when I accidentally canonicalized the main page "https://kv16.dk" to a page that did not exist.

4 months later the page got deranked, and you were not able to see the "main page" in the search results at all, not even when searching for "kv16.dk".

Then we discovered the canonicalization mistake and fixed it, and were able to get the main page back in the search results when searching for "kv16.dk".

At first after we made the correction, some weeks passed by, and the ranking didn't get better.  Google search console recommended uploading a sitemap, do we did that. However in this sitemap there was a lot of "thin content sites", for all the wordpress attachments. E.g. for every image in an article. more exactly there were 91 of these attachment sites, and the rest of the page consists of only two pages "main page" and an extra landing page.

After that google begun recommending the attachment urls in some searches. We tried fixing it by redirecting all the attachments to their simple form. E.g. if it was an attachment page for an image we redirected strait to the image.

Google has not yet removed these attachment pages, so the question is if you think it will help to remove the attachments via google search console, or will that not help at all?

For example when we search "kv16" an attachment URL named "birksø" is one of the first results