TECH TREE??

Hey, my name is luca and i have a proplem with the tech tree (option/tank)
idk, but in the middle i have 6 gears...
when i click on a 1+ no matter (green,red,blue,yellow)
NOTHING ... only the "effect" is working... pls help

 

try to reset your three,however it happened to me really much time just reset the game.(it's funny to spam clicks without doing noting but the sound and blue ligths at high fire rate xD) don't warry it will fix if you come again into the game or reset the three you won't have this problem for long time

 

Have you tried turning it off and back on again? o.o