Proofs forgot to include order of proposition in its Gödel number.
(Of course there can theoretically be bugs in a computer verified proof. If there are bugs in the verifier. But if 4 independent proof assistants verify a proof of a theorem, this is extremely unlikely.)
All of the computer-verified proofs of existence of [Gödel
1931] proposition I'mUnprovable left out the order of
proposition in its Gödel number :-(