to display error:Fatal error in gc Too many heap sections.
It's a problem regarding the garbage collector: your game is trying to use too much memory. The only thing I can tell you (at least, without viewing at your code) is to check that your game isn't allocating too many little objects (as an example, make sure that you're not allocating arrays at each Update iteration). I've also heard about the same problem occuring, sometimes, when using DestroyImmediate() on a material, because it could not free the memory occupied by the material itself.