One thing I would ask you to research is the idea of the 'unquenchable fire' and how 'the smoke rises for eternity'.
It reveals the punishment being of eternal standing.
For instance, if I burn away the plastic around a metal pot, that plastic is melted and ash, utterly destroyed. So my burning has changed it eternally. It cannot be unchanged.
This is alike to the touchstone process found in Old Testament scriptures, which is also spoken of in the New Testament as the 'threshing floor' and other such terms.
Again, I don't profess to be right. but that's what the bible says to me. go check them out
i'm sure you can find the material by searching the terms I have used on t'internet.