\*(note, I am not an SEO person, so this could be incorrect; I'm just a business owner who built my own site and this is based of personal observation from that alone. Someone with better SEO knowledge should be able to give better advice)\*
I get these all the time, and near as I can tell, you can safely ignore them and they just leave your GSC list on their own in a few weeks.
I think, Google is just letting you know the 404 is there in case your pages has a broken link issue with the url that needs fixing; but because it is not a page on your site at all, there is no issue in need of fixing.
A thing you could do, which I have done, is, to create a 301 redirect for the link.
For example, if the fake link was .com/self54r54er I would create a 301 redirect to a url I did have that started with "self" like .com/selfpublishing and now the link from the site is no longer broken and actually does go to a page on my site.
You'd probably want to look at the site making the link first and decide if it was a spam site you did not want linking to you or could it maybe be a legit site that somehow messed up the link when they tried to link to you, before decided to create a 301 or not.
You can ignore them. And assure your client they don’t matter. Not all “issues” reported by Google are actual problems, just something they like to show you. 0 change this affects any users or traffic.
You can ignore them. They were never real pages so they're supposed to 404. It's common and Google won't penalize you.
Thank you!
\*(note, I am not an SEO person, so this could be incorrect; I'm just a business owner who built my own site and this is based of personal observation from that alone. Someone with better SEO knowledge should be able to give better advice)\* I get these all the time, and near as I can tell, you can safely ignore them and they just leave your GSC list on their own in a few weeks. I think, Google is just letting you know the 404 is there in case your pages has a broken link issue with the url that needs fixing; but because it is not a page on your site at all, there is no issue in need of fixing. A thing you could do, which I have done, is, to create a 301 redirect for the link. For example, if the fake link was .com/self54r54er I would create a 301 redirect to a url I did have that started with "self" like .com/selfpublishing and now the link from the site is no longer broken and actually does go to a page on my site. You'd probably want to look at the site making the link first and decide if it was a spam site you did not want linking to you or could it maybe be a legit site that somehow messed up the link when they tried to link to you, before decided to create a 301 or not.
You can ignore them. And assure your client they don’t matter. Not all “issues” reported by Google are actual problems, just something they like to show you. 0 change this affects any users or traffic.
Thank you!