So my mod was working fine when i updated from 1.8.3 to 1.9.0 the mod started crashing when i tried to play on a world

So my mod was working fine when i updated from 1.8.3 to 1.9.0 the mod started crashing when i tried to play on a world. I tried reinstalling mcreator but it didn`t fix te problem. Now i have both 1.8.3 (to work on my mod) and 1.9.0 (to test the new features) if someone know how to fix te problem i will appreciate sharing the information with me.