Help please

Hello I have been trying to play minecraft City Challenge for the past day and 

every few minutes (not even sometimes seconds) my game keeps crashing where I have to close my game and restart every time. And when I try to build the skyscrapers the skyscrapers never spawn it take my money but the  building doesn't appear. All the progress I make in a the minute I get to play gets erased every time I have to restart. And I've tried just closing and opening the game but it keeps doing it every so often. Please fix this problem I just want to build my city