Is the setting "Clip to Graphics Extent" selected? And you're positive that the page size matches that of the layout elements?
Apologies if these seem like super basic questions, but I've overlooked them by mistake in the past and gotten similar results to what you've posted.
Is this a layout or a map? For a layout it's possible that the title is off the page. Anything outside the designed page won't be included in the export. In that case you just need to make the page size bigger.
If it is a map, you can use the Preview option for map export to see what is being included in the export. Everything else is hidden. In that case you can change the number of pixels to adjust the aspect ratio and get what you need visible.