Custom data fields not showing up?

Hi, I’ve just starting working with headspace for the first time, and am having an issue.

I’ve added a bunch of custom data tags to a page (the required Facebook Open Graph tags, to be specific), but none of them are showing up.

I put them in the Advanced group, added the data on the Edit page for the specific page and saved, but… nothing.

I know the plug-in is working otherwise, because I changed the page description and it is showing fine.

Thanks for any help.