letpassionburn on "Post author not showing on Twenty Sixteen theme"

I had this issue before, and uninstalled and reinstalled wordpress to eliminate any variables. The only modifications I have made to this theme so far were to add the logo and set a background. Even before I did this (meaning with a 100% fresh install and fresh twenty sixteen theme),when making a new post, the author and gravatar showed up the first time I went and looked at the post after publishing, and every time after that whenever I visit the page or the post, the page shows no author gravatar or info at all. Since doing a clean install did not fix this issue, I am stumped. I'm admittedly new to this, but I thought maybe the first time around it was because I had made so many modifications to the page. After it happening again on the fresh install with no mods, I'm not sure what to even look at as a problem. If anyone could advise, I'd greatly appreciate it. Thanks!