Strange problem on the home page

to some time it appear to me a sidebar on the homepage . I did not make any changes or maybe I did it by mistake but I do not understand how to remove it. from the screenshot you can see what i mean . What may have happened? I can not remove it except with css i think
this bar has also changed the margins of my front page


Hello there,

Probably it comes from one of your active plugins? To verify, try to temporarily disabling all active plugins at once. And re-run your test.

If you want me to check it directly, please share a link to your site.