11:28 AM PT -- A rep for Ulta tells TMZ ... "Ulta Beauty recently sent an email featuring Kate Spade New York fragrance with an insensitive subject line and for this, we sincerely apologize. Mental health is a very serious, important issue in this country, and not something we would ever take lightly. We apologize to the Spade family, our Kate Spade New York brand partners and to our guests. Thank you for understanding as we strive to do better."
Ulta is under fire after emailing out a promotion that collabs with Kate Spade ... one that refers to the fashion designer's tragic death.
People on Ulta's mailing list were shocked Sunday when a message came to their inbox saying "Come hang with Kate Spade" ... as you know, Spade hanged herself in 2018.
The Internet is going after the beauty company full bore ... with many wondering who the hell QC's stuff that goes out.