AncestryDNA does not currently list "Sephardic Jewish" as a region in its ethnicity analysis. Full list of all of the regions they report here: https://support.ancestry.com/s/article/List-of-AncestryDNA-Regions 

Presumably, until Ancestry updates the product to include a distinct Sephardic Jewish ethnicity (likely contingent on their being able to find reliable markers of who is Sephardic Jewish vs. non-Jewish Spanish, Greek, Moroccan, etc.), people of Sephardic origin end up with their AncestryDNA ethnicity estimate as some combination of various Southern European, Levantine, and North African regions.

All that said, you may want to take caution and review some of the posts in this forum which discuss the perils of taking consumer DNA ethnicity analyses - especially those produced by MyHeritageDNA - too seriously. Here's one recent thread: https://groups.jewishgen.org/g/main/topic/75824182#647450  

Adam Turner