What procedure would be my best option for my lumpy skin and minor-moderate skin laxity in stomach area? (Photos)

After second pregnancy, my skin now looks like an oatmeal-like fatty texture even though I do resistance training 3-4x a week which includes 10-15 min ab workouts. Im dealing with laxity and lumpy texture in middle of stomach primarily and a little bit of lower abdomen as you can see in the photos. Belly button may be herniated and definitely is lax. My weight is 115lbs and consider myself fit,but can't see results in stomach ever! Please help and thank you immensely for your advice in advance.