By default, OptimizePress disables all scripts from third-party plugins. This means that Nelio A/B Testing’s tracking script isn’t added in your tested page and, therefore, it can’t track any of your visitors.
Luckily, this is extremely easy to fix. Just go to your WordPress Dashboard » OptimizePress » Settings and then click on the Scripts And Styles tab. There you’ll find our plugin. Enable both our styles and scripts in the frontend as depicted in the following image:
and things should work as expected. Keep in mind that you may need to purge your cache and/or CDN if you use one.