Vegan... and still gaining weight.

I was on the birth control pill & I gained weight. I’m trying to lose it. However, I keep gaining weight!! I workout at least 5 times a week. Resistance training with 3-4 cardio sessions mixed in. I eat healthily most of the time. Why in the world am I still gaining weight?? I lost so much when I transitioned but that pill screwed me over! I eat relatively the same as I always have. Any tips??