ai-bookkeeper splits an Amazon settlement report into sales, refunds, tax, ads and fees. Every Promotion row was booked as a refund or discount, including the line that returns the tax on a discounted item. That line is a reduction in tax collected, so booking it as a refund overstated the discount and left sales tax payable too high by the same amount.
Promotion rows whose description mentions tax now go to sales tax payable. One new test covers it. The Amazon reference pages could not be fetched from the build sandbox, so this follows the amount-description names in the repo's fixture; no real settlement file has been tried.