Can't activate plugin

I’ve added WP Google Fonts to site with Coraline theme. I can add fonts in the Google Font Control panel (Settngs; Google Fonts) but when I go to Plugin, I don’t see the plugin so I can’t activate. I’ve research on WP support site and find that a plugin won’t show up if there is no/incorrect heading. “If you do not see the Plugin in the list of installed Plugins, most likely it is missing the “File Header””. I’ve compared the Google Font php and it does have a heading containing all the elements described in support document. What else should I be looking at to resolve this issue