Isaiah the poet is not talking about new moons being on the new earth. It's simply referring to (month to month moon) in the 1,000 year millennium. You agree?
Isa 66:22-23 “As the new heavens and the new earth that I make will endure before me,” declares the Lord, “so will your name and descendants endure. 23From one New Moon to another and from one Sabbath to another, all mankind will come and bow down before me,” says the Lord.
There will be no sun and moon on the new earth.
Rev 21:23 The city does not need the sun or the moon to shine on it, for the glory of God gives it light, and the Lamb is its lamp.
Isa 60:19-20 The sun will no more be your light by day, nor will the brightness of the moon shine on you, for the LORD will be your everlasting light, and your God will be your glory. Your sun will never set again, and your moon will wane no more; the LORD will be your everlasting light, and your days of sorrow will end.