I think you may be conflating the physical with the spiritual. Our bodies are mortal, but our souls and spirits are not. “It is appointed unto man once to die; and after this, the judgment.” So while believers may have true eternal life, in glorified bodies, the bodies of the unsaved will not be resurrected - but their spirits will still suffer the torments of hell.
That's claiming that we have eternal life in some form. That we don't really die. That's the lie..."you shall not surely die".
We have physical life only, right now. Our spiritual life happens later:
1Co 15:44 It is sown a natural body, it is raised a spiritual body. There is a natural body, and there is a spiritual body.
1Co 15:45 And so it is written, "THE FIRST MAN ADAM BECAME A LIVING BEING." The last Adam became a life-giving spirit.
1Co 15:46 However, the spiritual is not first, but the natural, and afterward the spiritual.
It really can't be much plainer. We have no part in immortality without Christ. The only "spirit" we have as non-Christians is that "spirit" that animates these lumps of clay we call "us".
Gen 2:7 And the LORD God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living being.
The breath of God is the spirit of life. When that spirit leaves us, we're lumps of clay again. We die and we rot. There is nothing left in us. We SURELY die. We don't "stay alive" in another form. We aren't immortal. We aren't "gods" that can live forever. Those are Satanic lies. We SURELY die without Christ.