[Getting Loads of errors and game won't start]

So whenever I load up the game it's giving me loads of error notifications stuff like 

TypeError Incompatible marshal file format (can't be read)

End of file reached

Then the title screen will show and after pressing enter the same stuff will show up and the last message before a force close will say

Script Pokemon Load Line 461 NoMethodError occurred undefined method last save for nil:Nil Class

 

I've tried taking the last save file from the folder and I've tried downloading the game again and opening it from the new download and the same thing still shows up