Biomutant has been updated to version 2.05 today on PS4, and 1.5.1 on PC. The full patch notes for this update can be seen below.
Biomutant has recently received a major update that has increased the level cap and implemented a number of fixes. The update that was released today is only out for PS4 and PC. This update patches the game to fix the issue with the new game plus character stuck inside the arc, and for fixing the new game plus menu that did not appear after beating the game. You can find out the details for this update with the patch notes given below.