Its basicly a file error
Evolve Stage 2- Properites on steam
Files- Verify files
If that does not help, its probably a loading bug, they are kinda rare. its a 1-2 day lasting bug. (probably servers)
if none of that works re-install the game. You probably didnt download the whole thing witch is kinda normal.
(if none of that works than... Sorreh~)