How did you reach L90? I did 99.9% of everything in my first time through the game, DLCs included, and only reached L54 before starting my NG+.
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@OP: You probably know this, but here's what yuou need to do to start a NG+
Load your most recent save, from anytime after you completed the story.
Make a new manual save.
Go back to the main menu and start a new game, pick your difficulty/tutorial options, and select “New Game+” when given the option. Select the save game you just created to import for the NG+—other saves won’t work.
Sounds like you already finished one NG+. If you did, then everything is working as intended.
If you didn't, then it's a problem. What's your platform (PC [GOG, Steam, Origin], PS4, Xbox One)?