First, when the epistles were written there was no "bible" as we know it today so obviously there was no command about something that did not yet exist.
Second, the office of apostle ( the 12 selected to speak under the authority of Jesus who by qualification HAD to be a physical eyewitness to the resurrection of Jesus)...
Why do you believe they had to be physical eyewitnesses? Is that found in written scripture?
What do you believe than concerning the following verses and the work of their ministry? Is all of that work done already so that no one else needs or receive such help?...are all dead now and that's not a birthright passage so that's a non sequitur comparison. There are no more offices of prophet, apostle or high priest. ( no more human authority direct of God)
"And he gave some, apostles; and some, prophets; and some, evangelists; and some, pastors and teachers;
For the perfecting of the saints, for the work of the ministry, for the edifying of the body of Christ:
Till we all come in the unity of the faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the stature of the fulness of Christ:
That we henceforth be no more children, tossed to and fro, and carried about with every wind of doctrine, by the sleight of men, and cunning craftiness, whereby they lie in wait to deceive;" Eph 4:11-14
We have the written word and we have the Holy Spirit to teach and guide us.