partner won’t initiate

I f20 and my partner m21 have been dating for a few years now and for the past year or so we’ve basically had a dead bedroom. I noticed around the beginning of this time that he had completely stopped initiating and so I gradually slowed down on my side too because I didn’t want our sex life to be one sided, we now go months without sleeping with each other because I’ve given up. We’ve had multiple conversations about this and he keeps insisting he does want to be intimate with me and he’s trying but there’s just nothing. He insists it’s nothing I’m doing wrong and that he can’t seem to find an issue that would specifically be causing this, so now I’m just left feeling neglected because it doesn’t feel like he’s taking our conversations seriously when we have them as there’s no progress afterwards. What can I do to encourage him because I’m out of ideas and coming to the end of this rope man.