I'm getting an error that is telling me this (see below). I don't know how to fix it or where to even begin. I can load the mods just fine in singleplayer but whenever I try to start up my server I get this error. Does anyone know how to help?
crash-2024-03-19_22.06.11-fml.txt

Description: Mod loading error has occurred

java.lang.Exception: Mod Loading has failed
at net.minecraftforge.logging.CrashReportExtender.dumpModLoadingCrashReport(CrashReportExtender.java:60) ~[forge-1.20.1-47.2.0-universal.jar%23626!/:?] {re:classloading,pl:rei_plugin_compatibilities:B}
at net.minecraftforge.server.loading.ServerModLoader.load(ServerModLoader.java:37) ~[forge-1.20.1-47.2.0-universal.jar%23626!/:?] {re:classloading,pl:rei_plugin_compatibilities:B}
at net.minecraft.server.Main.main(Main.java:125) ~[server-1.20.1-20230612.114412-srg.jar%23621!/:?] {re:mixin,re:classloading,pl:rei_plugin_compatibilities:B,pl:mixin:A}
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?] {}
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[?:?] {}
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?] {}
at java.lang.reflect.Method.invoke(Method.java:568) ~[?:?] {}
at net.minecraftforge.fml.loading.targets.CommonLaunchHandler.runTarget(CommonLaunchHandler.java:111) ~[fmlloader-1.20.1-47.2.0.jar%2369!/:?] {}
at net.minecraftforge.fml.loading.targets.CommonLaunchHandler.serverService(CommonLaunchHandler.java:103) ~[fmlloader-1.20.1-47.2.0.jar%2369!/:?] {}
at net.minecraftforge.fml.loading.targets.CommonServerLaunchHandler.lambda$makeService$0(CommonServerLaunchHandler.java:27) ~[fmlloader-1.20.1-47.2.0.jar%2369!/:?] {}
at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:30) ~[modlauncher-10.0.9.jar%2355!/:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:53) ~[modlauncher-10.0.9.jar%2355!/:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:71) ~[modlauncher-10.0.9.jar%2355!/:?] {}
at cpw.mods.modlauncher.Launcher.run(Launcher.java:108) ~[modlauncher-10.0.9.jar%2355!/:?] {}
at cpw.mods.modlauncher.Launcher.main(Launcher.java:78) ~[modlauncher-10.0.9.jar%2355!/:?] {}
at cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:26) ~[modlauncher-10.0.9.jar%2355!/:?] {}
at cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:23) ~[modlauncher-10.0.9.jar%2355!/:?] {}
at cpw.mods.bootstraplauncher.BootstrapLauncher.main(BootstrapLauncher.java:141) ~[bootstraplauncher-1.1.2.jar:?] {}

First off this ticket tracker is for OptiFabric. The error you are getting is for Forge and thus you will need to go to the Forge Loader Ticket site to get help and/or help from the server type that you are running as well (i.e. Bucket, Paper, Forge, etc...)