The browser seem to be blocking the session initialization inside Iframe. Because the course is getting loaded from a different website (learnzone.edubrite.com), some browsers (especially Safari) implement this policy, to block the third party websites from dropping the cookies from inside Iframe which can be used for tracking user's activities without user's knowledge.
But since learnzone.edubrite.com isn't a malicious site, you can instruct the browser about it, by opening learnzone.edubrite.com url in a new window once. Once you do that, browser will understand that you recognize this website, and are willing to load content originating from there. From that point on, you will be able to access the courses without any issue.Click Here to Open learnzone.edubrite.com after that refresh the browser to reload this page.
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