Error when loading survival world

I have this error when loading a survival world / open a word 
I'm on the 2020.5 version of mcreator and I use the 1.12.2 generator 
I have this error but idk why he say it's because I have a overlay but I never set a overlay and I have try put a backup / reload the code nothing same error 

---- Minecraft Crash Report ----
// I bet Cylons wouldn't have this problem.

Time: 3/1/21 2:35 PM
Description: Unexpected error

java.lang.NoClassDefFoundError: net/mcreator/customrandomitem/procedure/ProcedureAmmoOverlayDisplayOverlayIngame
    at net.mcreator.customrandomitem.gui.overlay.OverlayAmmoOverlay$GUIRenderEventClass.eventHandler(OverlayAmmoOverlay.java:46)
    at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_26_GUIRenderEventClass_eventHandler_RenderGameOverlayEvent.invoke(.dynamic)
    at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90)
    at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:182)
    at net.minecraftforge.client.GuiIngameForge.post(GuiIngameForge.java:914)
    at net.minecraftforge.client.GuiIngameForge.renderHelmet(GuiIngameForge.java:288)
    at net.minecraftforge.client.GuiIngameForge.renderGameOverlay(GuiIngameForge.java:135)
    at net.minecraft.client.renderer.EntityRenderer.updateCameraAndRender(EntityRenderer.java:1151)
    at net.minecraft.client.Minecraft.runGameLoop(Minecraft.java:1208)
    at net.minecraft.client.Minecraft.run(Minecraft.java:441)
    at net.minecraft.client.main.Main.main(Main.java:118)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97)
    at GradleStart.main(GradleStart.java:25)
Caused by: java.lang.ClassNotFoundException: net.mcreator.customrandomitem.procedure.ProcedureAmmoOverlayDisplayOverlayIngame
    at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
    ... 23 more
Caused by: java.lang.NullPointerException