Hi @edmundspr!
Have you done any initial troubleshooting yet? It’s possible that there might be a conflict with one of your current plugins or your theme.
Try disabling all of your plugins except Sensei. Then try testing again to see if the issue persists. If that resolves your issue, you can find what was causing it by enabling each plugin one by one while continuing to test.
If that doesn’t help, you can also try switching to the Twenty Twenty theme via Appearance > Themes, and test again. If the issue is resolved then you know it’s a problem with the theme, and you’ll need to contact the theme author for further assistance.
Please also try going to wp-admin > Sensei LMS > Settings > Courses, and check if Enable theme styles is enabled?
We’ve seen cases where the custom theme styles may block the quiz from loading.
Let us know how it goes.
