tabs not showing

Hi,
I added 2 Tabs elements on a page; fullwidth row 1/2 + 1/2. In the backend editor they appear and work fine. When I publish the page it only shows two empty text boxes, that I included within the tab, where the content should be. No tabs showing at all along the top.

I was able to publish it once but when I went back to edit it stopped working when I published the text edits. I tried to delete the Tabs and row and rebuild with no luck.

I have included a screenshot.

Regards