Hello :)

So...i´m really enjoying the game and i´d like to start again, with my level 100 on new game plus :D (want that 100lvl armor) but game says, that it wasnt finished on the save i´m choosing for new game plus. I´m pretty sure it was tho. Any ideas what to do with it, or is it just because game cant start with level 100 ?:D

You can't have NG++, only NG+.

There's actually a mod that allows it, check https://www.nexusmods.com/witcher3/mods/2292
I haven't tried it, so can't say anything about it.
Check the posts and bug links for additional info.

Thank you : i´ll try that :D