Sorry I’ve been away.
I fixed the problem, by going to Settings>Reading>Featured Content.
That’s where I was able to change the tag name to ‘Featured’, it was blank by default (which was causing the problem).
I am not able to do it through Appearance>Customize>Featured Content. It just doesn’t show up there for me, the only option I have is Layout (Grid or Slider).
FYI, haven’t had to disable Jetpack.
Thanks for everyone’s help/input.
