Icon shows up before every article

Every article entered into the web site has an image, first one, which does not exist and it shows an empty frame. Can you please tell me how to avoid this image appearing?

You have some zombie article? Clear trash in article manager , if I understood good

You can check what I say at the arion.hol.es/ where the article Commerce in the content position has one small icon - blank - and I have not added this in the article.

If you need to go at the back office of joomla the user is admin and the password is smart3935.

this is a demo site and not my site so be free to do whatever you like

I opened image dialog in article edit screen, made sure all is blank, clicked on insert, saved article and it disappeared . Maybe it was some leftover in db.