404 on some attachment links – yoast SEO

Hello,

I created a new WordPress theme from scratch for this client.
After few days google search console started to send notifications of 404 errors for some attachment urls, such as:
/zmyslowy/
/masaz-kaszmirski-big/
etc.

Those links give 404. Of course I can turn on the redirect in SEO -> Search Engines -> Media, to make the attachments sitemap disappear. But this would be a workaround, not a fix.

I need help to find where those attachments are defined. Why there are such links with such names.

Another information. I went to wp-admin -> Media -> Library and I search for the images.
I managed to find for example this image.
That image, if I click on it in the Library, and I click on “show attachment link”, it goes to this link, which is the attachment link that gives 404.

How is that possible that an image exists and its link gives 404?

If I choose some other images from the library and I click the attachment URL, they work fine, such as this one.

Please help me to find the root cause of this problem.

Thanks

• This topic was modified 4 years, 8 months ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Developing with WordPress topic

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