World Crashes when loading, other worlds work fine. I have the current updated version of minecraft for iphone 7

One of the world I have, does not open. It closes the app as soon as the loading stage begins all the other worlds I have work fine. Please help me find what is the problem. I tried to reinstall the world by deleting the app, but the problem still continues. Please help me, I have worked in this world for 3 years.
Thank you.