Husband always had single member llc for real estate rental.  This year he comes in and has changed information on the secretary of state website for 2023 to add wife to make a partnership. He never filed for a new EIN number and did not know the filing requirements for partnership and so there was no extension filed for it.   Can it be filed still as a single member llc for 2023 since he never did apply for the ein.

thx

Michele