That would mean a great-great-great grandparent was Jewish, going back five generations. most people have a little bit of something surprising in their DNA if you go back that far.
some of the people working at these companies have admitted that they fudge data for well known people.
Usually to upset them
This sounds like 23andme. Several people have been told they are Ashkenazi from 3 or 4000 years ago. Don’t know the validity.