Provocar means "to provoke," but in romantic contexts like this song, it often takes on a lighter, more playful meaning, closer to "to tease" or "to entice."
In the lyrics, Alvaro Soler sings, "Loca, loca, loca cuando me provoca" (Crazy, crazy, crazy when she teases me). He uses this word to describe how his love interest's actions make him lose his reason, perfectly capturing the song's theme of thrilling, irresistible attraction.
Alvaro Soler is completely gone for someone in this song, and he doesn't care who knows it. He's so head-over-heels that he admits, "Loca, loca, loca cuando me provoca / Pierdo y pierdo la razón" (Crazy, crazy, crazy when she provokes me / I lose and lose my reason). It's an intense, all-consuming kind of love where he can't even sleep without her.
His friends are worried, telling him "que tú no me haces bien" (that you're not good for me), but he's not listening. For him, it's simple: "Para mí esto es amor" (For me, this is love). He just wants her to stay the night and be there in the morning. He thinks the whole thing is worth it for just one kiss, which tells you everything you need to know about how he feels!