Husband

My husband is not much into sex. I try everything I can to try bring him close to me to get intimate but he doesn’t seem to be into it and only haves sex during fertile window. Could this be due to a fertility issues as during 1st year of wedding he was great in the bed and would want to have it more often. Also now he always wants me on top and does no foreplay for me and I feel like I’m doing all the work. I’m starting to get very frustrated but I do love him a lot and I know he does love me too. Any suggestions are welcome please 🙏🏼