Links not working in top post only

I cannot get my links (not even the permalink in the title or the link to the comments)to work in the top post only. I think this started happening when I upgraded to the latest version of WordPress, but I can’t be 100% sure.
I have tried deactivating all my plugins and the links still don’t work. I reinstalled WordPress and even updated my theme and the problem persists.
I’ve been marking posts without links as “sticky” so the ones that need to link out will work, but this is not an ideal solution.
I don’t know what else to try.