I play on Minecraft Pocket Edition on IOS and i’m having an issue with my worlds. Every time i load a world up, it goes to the generating world screen, shows the loading bar filling up. The bar goes away and i’m just left at the “generating world” screen with the fact and it stays there not letting me into my world. 

Edit: I’m able to create worlds and load those for the first time, but if i leave the world and try go back in to it, same thing happens

The images below show what i’m talking about