Hi mattiesmom
Welcome to the boards
Firstly has Mattie had any 'bad' experiences with taking a bottle, babies can associate negative/positive experiences with taking bottles, breast, etc....
What feed during the day is he refusing? Are you on a 3 or 4 hour EASY? He is actually hungry when you feed him? One sign that he is ready for a 4hr (if your are not already on it) is that he would not be hungry at the 3 hour mark.
HTH's