[Server Error?]

I'm trying to get my friends out of vanilla minecraft and decided to try running a B-Team server and have had minor success in the past years ago but in this most recent attempt i keep recieving the exact same error, does anyone have any idea what I'm doing wrong?

cmd prompt:

C:\Users\jkspi\Desktop\BTeamserveryay>java -Xmx3G -Xms2G -jar BTeam.jar nogui
A problem occurred running the Server launcher.java.lang.reflect.InvocationTargetException
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:567)
        at cpw.mods.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:48)
        at cpw.mods.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:17)
Caused by: java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to class java.net.URLClassLoader (jdk.internal.loader.ClassLoaders$AppClassLoader and java.net.URLClassLoader are in module java.base of loader 'bootstrap')
        at net.minecraft.launchwrapper.Launch.<init>(Launch.java:33)
        at net.minecraft.launchwrapper.Launch.main(Launch.java:27)
        ... 6 more

C:\Users\jkspi\Desktop\BTeamserveryay>pause
Press any key to continue . . .