Quizz question doesnt charge

Hi,
I’m sorry to use this way for contact you but I need your help… I’m using Lifter LMS ( free for the beginning). I have created a course, lesson and quizzes. Courses and lessons are working but when the membership goes to make the quizzes the question doesn’t charge… I don’t understand why because the course is not free, questions are okay…

/llms_quiz/inventaire-des-symptomes-attention?attempt_key=MTAyODB8MTAyNzl8MQ=:1 The certificate used to load https://lifeline-tdah.fr/llms_quiz/inventaire-des-symptomes-attention?attempt_key=MTAyODB8MTAyNzl8MQ= uses an SSL certificate that will be distrusted in an upcoming release of Chrome. Once distrusted, users will be prevented from loading this resource. See https://g.co/chrome/symantecpkicerts for more information.
jquery-migrate.min.js?ver=1.4.1:2 JQMIGRATE: Migrate is installed, version 1.4.1
inventaire-des-symptomes-attention?attempt_key=MTAyODB8MTAyNzl8MQ=:711 Mixed Content: The page at 'https://lifeline-tdah.fr/llms_quiz/inventaire-des-symptomes-attention?attempt_key=MTAyODB8MTAyNzl8MQ=' was loaded over a secure connection, but contains a form that targets an insecure endpoint 'https://feedburner.google.com/fb/a/mailverify'. This endpoint should be made available over a secure connection.
jquery.plugins.js:380 Trying to start timer when countdown already at 0
inventaire-des-symptomes-attention?attempt_key=MTAyODB8MTAyNzl8MQ=:410 GET https://lifeline-tdah.fr/llms_quiz/Array 404 ()
llms.min.js?ver=4.9:1 Uncaught TypeError: Cannot read property 'append' of undefined
    at Object.success (llms.min.js?ver=4.9:1)
    at i (jquery.js?ver=1.12.4:2)
    at Object.fireWith [as resolveWith] (jquery.js?ver=1.12.4:2)
    at y (jquery.js?ver=1.12.4:4)
    at XMLHttpRequest.c (jquery.js?ver=1.12.4:4)

Thanks a lot
Maxine

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