Why is my Husband's tax preparer telling him that because we file married separate that I shouldn't have included his information on my tax return?

Even though the rules clearly state that I have to provide his name and social, and I have filed the same way every year since we've been married and now she's saying that's why his state return is getting rejected, and it never has before, filing the exact same way as we have, Married/Separate, every year before?