Husband has a hard time getting it up

My husband has a very hard time getting and maintaining an erection. We've been married almost a year but he says he's had this issue for a few years now. I thought it was me at first but he swears up and down that he is turned on by me. He says it's like his mind is turned on but he has a hard time physically. He's only 27. I think he needs to see the doctor but he doesn't😒 has anyone else experienced this with a young partner?