Did it three or four times throughout the game. For no apparent reason it eventually stopped. I walked away a couple of times just to let it keep going till it decided to stop. Quite frustrating, but I did beat it in one try, just took me about 45 minutes.
Happened to me also. On my first attempt, I lost all the boosters I had built up by going through 5 levels at the first attempt. Have also wasted the boosters I used to achieve this !!! Refund please.