J.H.
I don't know if you tried this, but when i first tried giving my daughter formula to supplement my breastmilk supply at about 8 months, she wouldn't have anything to do with it. I realized that I was giving it her at room temp or cooler, but once I started warming it up, she took it like a champ. Another friend of mine who also breastfed her daughter found that her daughter would only take formula from a bottle that had a certain type of nipple. Like us adults, babies can also be fickle. So whether it be the kind of formula, or how it is served, its surprising that these little ones already have preferences at such a young age. good luck!