Timothy was not an Apostle.
He was Paul’s chief disciple, but the office of Apostle ended upon John’s death.
The Revelation makes it clear that there are only 12 apostles.
Luther complained about the Book of Revelation: “to my mind it bears upon it no marks of an apostolic or prophetic character... Everyone may form his own judgment of this book; as for myself, I feel an aversion to it, and to me this is sufficient reason for rejecting it.” (Sammtliche Werke, 63, pp. 169-170,