How do you get to level 22 on orb 2

There is no level 22 on Orb2 or Orb2 TNL.
There are Bonus Levels including belts and endless levels.

There is no level 22. There is not actually a level 21 -- it is the end screen.
There are 20 playable levels and 5 bonus challenge levels on the main menu.
(to access, enter the level 21 code, which is 51210)