Will this affect a persons unemployment PLEASE HELP

If a person has a hobby where they buy things and then sell them for a hight profit but is colllecting unemployment do you have to report that to unemployment . I wasnt sure and didnt want my friend to get in trouble fomr it she basicly buys products for cheap froma wholesaler andthen advertises the products to make a profit but its a hobby . Should or does she have to let unemployment know about this .any advice i would appreiate it alot thanks alot