Millennial reign and New Heaven and New Earth

Why does Revelation 21:1 talks about the new heavens and new earth after the millennial reign described in Revelation 20 while Isaiah 65 seems to indicate that the new heavens and earth come first before the millennial reign because there is still death on Earth (vs20) at that point? The end of Revelation indicates that death is gone seemingly after the millennial reign when the new heavens and earth are created. > Now I saw a new heaven and a new earth, for the first heaven and the first earth had passed away. Also there was no more sea. (Revelation 21:1 NKJV) > “For behold, I create new heavens and a new earth; And the former shall not be remembered or come to mind. “No more shall an infant from there live but a few days, Nor an old man who has not fulfilled his days; For the child shall die one hundred years old, But the sinner being one hundred years old shall be accursed. They shall build houses and inhabit them; They shall plant vineyards and eat their fruit. They shall not build and another inhabit; They shall not plant and another eat; For as the days of a tree, so shall be the days of My people, And My elect shall long enjoy the work of their hands. They shall not labor in vain, Nor bring forth children for trouble; For they shall be the descendants of the blessed of the Lord, And their offspring with them. “It shall come to pass That before they call, I will answer; And while they are still speaking, I will hear. The wolf and the lamb shall feed together, The lion shall eat straw like the ox, And dust shall be the serpent’s food. They shall not hurt nor destroy in all My holy mountain,” Says the Lord. (Isaiah 65:17‭, ‬20‭-‬25 NKJV)