LogFAQs > #965159490

Remember that they are constantly updating what those markers mean. Perhaps their original assessment found that their was a trend toward being black in your genetics when you come from that area, but in later assessments found that other markers are needed for that trend to carry and dropped the association on you.

Their data is constantly being updated with new people taking the test, so their results are going to get progressively more nuanced.

There's also the chance some guy sued for their heritage being called in to question against their own records, Ancestry couldn't back their claim sufficiently to have the case thrown out, so they settled out of court and tightened up the boundaries for claiming certain backgrounds.