Why does Vscode still give me package not found error with Weka after referencing the JAR file in classpath? [closed]

This is my MRE.

Here is how my project is structured

Project structure here

Settings.json file

{
  "java.project.referencedLibraries": [
    "lib/weka.jar"
  ]
}

Main.java

import weka.core.Instances;

public class Main {
    public static void main(String[] args) throws Exception {
        // Load a dataset (replace with your .arff file)
        System.out.println("Hello");
    }
}

main.class

// Source code is decompiled from a .class file using FernFlower decompiler (from Intellij IDEA).
public class Main {
   public Main() {
   }

   public static void main(String[] var0) throws Exception {
      System.out.println("Hello");
   }
}

The error coming from main.java is

Unused Import(hints(1): 1:1-1:28)
package weka.core does not exist(errors(1): 1:8-1:12)
The import weka.core.Instances is never usedJava(268435844)
package weka
weka

img of error

upon running

javac -cp .;lib/weka.jar src/Main.java

compiles with no issues. this cmd built a Main.class in my src folder.

however, upon running

java -cp .;lib/weka.jar Main

the error is

Error: Could not find or load main class Main
Caused by: java.lang.ClassNotFoundException: Main