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Reported problems over the past 90 days
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Something wrong that is not listed?
- Reload the page first — that clears most problems.
- Your work is also saved on your own device, so a failed save does not lose it. It is sent again automatically the next time you open a lesson.
- If saving is failing, avoid clearing your browsing data until it is fixed — that is the copy we recover from.
- Still stuck? Email xchee-01@nus.edu.sg and say which course and which lesson.