Last updated 29 July 2026
If you spot a substantive mistake in a practice set or proprietary worked explanation, please email [email protected].
Include the paper ID shown on the cover page, the set name if available, the question number, and a short description of what appears to be wrong.
We will review all substantiated reports carefully.
Where a substantive issue is confirmed, we may correct the issue and provide a refund or replacement at our discretion.
This applies to confirmed substantive errors in the practice set or explanation. It does not apply to differences in preferred wording, teaching style, or cases where the material is accurate but not the format a user expected.