Smooth Slider – text not displaying

Often, but not always, the text does not display on a slide. Sometimes, recreating the post will correct the problem, but not always — as is currently the case. The text does show up in the coding when I inspect the code in a browser, but does not display on the slide.
The settings are exactly the same as in other posts that are functioning properly.

https://www.ads-software.com/plugins/smooth-slider/