Loading 1.7.1.0 world to 1.8.0.24 crashes game

I am trying to update some old worlds from 1.7.1.0. I realised everything above 1.8.0.24 crashes the game when i try to load the worlds (or update it)... I use a bedrock launcher (https://bedrocklauncher.github.io/) to go back in older versions... If u cant fix, do you know another way to update the world? Thanks!