Boyfriend will NOT kiss my neck

So I know this is quite weird but bare with me!  I told him at the beginning of our relationship some hotspots because he asked. One main hotspot is my neck. Every time we start getting sexual he refuses to do anything involving kissing besides the lips. I've been with guys who have sucked on my boobs and gave me hickeys for days on my neck. Which drove me insane with pleasure!! We've been together four months and I recently asked him to just try it out and I practically had to beg for him too. Once he did it, it was about 5 seconds before he told me it was weird and he didn't wanna do it again. My neck is basically the one thing that gets me in the mood besides him messing with down there. What do I do?? Help! Please no judging!