Why doesn’t he want to have sex with me?

I’m so confused on why my boyfriend doesn’t want to have sex with me. We have been together for months and we are long distance. We talk sexual and he tells me all the sexual things he wants to do to me but when we are together he only fingers me and eats me out. He says that he just wants me to be happy but I tell him I’m ready to have sex and I know he wants it too. I just don’t know why he won’t let me do anything with his dick.