Going down

How do you get your man to go down on you? I’ve been with my boyfriend going on 3 years, when we started talking he said he’d go down on me but when I asked about it he said he didn’t fell good just wait for another time so I waited a bit asked again a couple months later and he said no he doesnt do that so why say in the beginning that you would than not do it. I give him head all the time why can’t I get it too. I love him but shit I wanna cum too man