Game super, but complete system locked

I have downloaded the game for my daughter four years on the Kindle Fire HD. After the trial I have updated to the 2.69 version expensive. The game content is really great and the Speil easily understood even for the little ones. After about 20 minutes the game was hanging at once and I was able to boot the system again only with a restart of Kindle.
After booting up the Parental Lock in the Kindle was active. Since I had never set this, I had no password also. Also resetting the system was not possible without this password.
But thanks to the super customer service, the problem could be solved quickly and now everything is running again. However, without the game. The purchase price was paid back immediately.