Practice Tests not working on multiple browsers & devices

Hi, none of the practice quizzes are working for me where they have worked fine in the past using the same set-up. I have tried Chrome, Firefox, Edge, IE all on windows 10. Have upgraded Adobe flash but still not working. Have also tried from an android device with no joy. Example links: https://opentuition.com/acca/f7/f7-chapter-7-questions/ https://opentuition.com/acca/f7/f7-chapter-10-questions/ https://opentuition.com/acca/f7/f7-chapter-18-questions/ https://opentuition.com/acca/f1/f1-chapter-1-questions/ https://opentuition.com/acca/f1/f1-chapter-11-questions/