what should i do

it took me FOREVER to get my 5mth old on somewhat of a schedule..well im with her during the day so her schedule stays the same but i have class mon-wed 5:30-9:20 gabby is suppose to have her dinner(BF) at 6:00 my SO will not feed her BF dont ask me why! he as no schedule for her at night which i had one before i started school..now the days i dont have school she wont eat at the time she usually did or go to bed because her dad doesnt stick to the schedule i had for her in the beginning..what would u do? i dont know why he wont feed her the BF for dinner