By chance I noticed that your situation is much more complicated:
- students navigating the quiz through browser "back" and "forward" buttons (user error)
- answers not saved (user error or theme error)
- server overloaded (user error - impatient students or server not powerful enough)
- indeed students "sharing" accounts
Source: https://moodle.org/mod/forum/discuss.php?d=414712.
That is something for a forensic expert!
- students navigating the quiz through browser "back" and "forward" buttons (user error)
- answers not saved (user error or theme error)
- server overloaded (user error - impatient students or server not powerful enough)
- indeed students "sharing" accounts
Source: https://moodle.org/mod/forum/discuss.php?d=414712.
That is something for a forensic expert!