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A wrong score. The lesson and roughly when you attempted it. We can look at exactly what was scored and why.
A lesson that is wrong. Which claim, and what you think it should say. Corrections to the material are welcome and get fixed.
Billing or refunds. The email on the account.
Your data. An export, or a deletion. See your data.

Answered directly, by the person who built the thing you are asking about. Start with privacy, which is written to answer most of them.