I have such a problem but it turned out to be my SD card was faulty. I bought a new card from SanDisk working great now. Same situation to the worlds. I downloaded an app on Google Play called Inventory Editior which allows you to change back to Survival mode and rename it. Some people said it was a cheat, but I think using it in good deed doesn't count. Most importntly is whether you want to play the game sseriously. Hope this helps.
Jason Chiu
I have such a problem but it turned out to be my SD card was faulty. I bought a new card from SanDisk working great now. Same situation to the worlds. I downloaded an app on Google Play called Inventory Editior which allows you to change back to Survival mode and rename it. Some people said it was a cheat, but I think using it in good deed doesn't count. Most importntly is whether you want to play the game sseriously. Hope this helps.