Need advice

Hello I'm on a weight loss adventure and I'm a couple weeks in, however my stomach and lower back are still problem areas as always. I'm 21, 5'4 and about 160lbs. I'm going to Aruba late next month and I want to feel super confident with my body and I'm not there yet. Any advice on how to cut more weight or detox things/workouts etc. I do about 30min of cardio a day and also do some weights but I feel like I've plateaued. Please help me, I want to look super sexy in a bikini with a rocking fit body!