Getting java.lang.ClassCastException while trying to attach IntelliJ debugger

[vrozental]

I followed the instructions to setup the AttachMe using port address 127.0.0.1, because of the a problem with the bind address. Then I ran the Play application using sbt start. The AttachMe throws an exception:

AttachMe listening for debuggee processes on port 7857
java.lang.ClassCastException: class com.intellij.debugger.impl.attach.JavaAttachDebuggerProvider$ProcessAttachRunConfiguration cannot be cast to class com.attachme.plugin.AttachmeDebugger$ProcessAttachRunConfiguration (com.intellij.debugger.impl.attach.JavaAttachDebuggerProvider$ProcessAttachRunConfiguration is in unnamed module of loader com.intellij.ide.plugins.cl.PluginClassLoader @44774fa2; com.attachme.plugin.AttachmeDebugger$ProcessAttachRunConfiguration is in unnamed module of loader com.intellij.ide.plugins.cl.PluginClassLoader @1412d19c)
	at com.attachme.plugin.AttachmeDebugger.attach(AttachmeDebugger.java:27)
	at com.attachme.plugin.AttachmeRunner.onDebuggeeProcess(AttachmeRunner.java:59)
	at com.attachme.plugin.AttachmeRunTask.runServer(AttachmeRunTask.java:67)
	at com.attachme.plugin.AttachmeRunTask.run(AttachmeRunTask.java:39)
	at java.base/java.lang.Thread.run(Thread.java:834)

What does cause to the exception? How to fix it?
Thank you!