Newborn eats alot

dee • Wife 💍 Mom of 2 boys
I have a 5 day old new born and it seems like no matter how much he eats, it's not enough. He can eat 2, 59 ml bottles in less than an hour. Ive been giving him breast milk and topping him off with formula because I'm not producing enough but he's going through formula like crazy. Any advice on what I should do?