This song has been removed! The reason for removal was due to it being a promotion.
What Is Love?, a famous anthem of the 1990s, was allowed to be remixed by Project 46 with direct permission from Haddaway himself. Released under the Razor & Tie label, Monstercat uploaded the track as a promo for Project 46, showing how far they had come. Unfortunately, because this was a promo, it was deleted.
To find a remix, find the artist's name under the alphabetized list. All of the artist's remixes are listed with their name. For example, Morgan Pages's remix of 'Downhearted' would be under the 'M' tab, since the artist's name begins with the letter 'M'.