Husbands sex drive

My husbands sex drive is going down. We used to have sex at least 5x a week now we’re lucky if we do it 2x a week. We’ve been married 5 years. Our relationship is strong but I still have a high sex drive and I feel that he doesn’t anymore.

The other day I gave him a handjob and he got hard af but didn’t do anything. It was early morning and old him would’ve banged me right there but he just lay there and eventually we went back to sleep. He’s 37. Is that normal?