Girls, I really need help! The baby is not getting enough milk, in a m…

Girls, I really need help! The baby is not getting enough milk, in a month I managed only 100 grams. I need to supplement with formula after breastfeeding, the problem is that the child refuses the bottle ? what to do, I don't know, I feed him formula, he cries, gives me breast and doesn't get full either and also gets fussy! Help me with advice please.