My 3 month old is breastfed 99% and has been given the occasional bottle of formula since he was 1 week. A week ago he started refusing to take it. I thought it might be the formula so changed brand but he's still not taking it. He will drink the formula when it comes out the bottle in to his mouth but won't suck on it properly. It's the Tommee Tippee ultra bottle with the closer to nature teat so it's more breast like. Is it possible for a baby to go off using a style of bottle?