Partnership filed form 1065 in 2018 and made conversion on Sept 2018 to "S"     effective Jan 1,2019

By error the new converter "S" corporation  open  1/20/19 as member 2 LLC and 2 Corporation one one of the coporaion  was converter  "S"  and the other was not and remain an "C: due to the closing of the IRS and then forgot do the conversion until applied in December 2020.and as such is automatically status "s" revocation, cancelled the "S"" status,

Question: Due to the cancellation of the "S" status what should be filed now a form 1065 partnership or file form 1120 as corporation

Thanks for the help.