Not wet enough

When I first started hanging out with this guy, even though there was nothing going on at all at that time, I’d be dripping wet by the time I left his place because I was lowkey trying to hook up with him but didn’t have the balls to try anything. A few weeks later, he made a move completely out of nowhere and we started hooking up. It’s just a friends with benefits situation but it’s been going on since April. I’m still very sexually attracted to him and the sex is great but I never seem to be that wet anymore, to the point where he ends up having to spit on my vulva to be able to penetrate me. Any idea why this could be happening/any tips to help?