I followed your recommendation, and it did not work, but I am playing from my tablet, I do not have boosters, they are locked with a padlock, I am at level 942, any other solution? thanks
If you are playing on a mobile device, here is a solution that was given out for this glitch ---> RE-PLAY the levels in which those boosters are unlocked.
Here is the list of those levels for you::
Level # 5 ---> to unlock Shovel;
Level # 8 ---> to unlock Tractor Booster;
Level # 13 ---> to unlock +1 Bonus;
Level # 23 ---> for Hunter (the single colored cropsie collector);
Level # 31 & Level # 72 ---> for rest of the two boosters
