Java is asking to return a value even when the value is returned in the if-else ladder

I was trying to code AVL tree in java and something has just shaken my understanding of basic programming. Why does Java force me to return a value when I already have a return statement in the else block of the if-else ladder. I tried debugging and it works as expected, it never goes to the returns statement outside the if-else blocks. I have been working on java and never realized this. I am not even sure if this was always there or is it something new? I also read a few blogs which say that you don't have to return a value if you have returned it from the else block.

The error which I get is I skip the last return statement.
Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
    This method must return a result of type AVLNode

https://javahungry.blogspot.com/2019/12/missing-return-statement-in-java.html checkout the last example on this link.

public class AVL 
{
    AVLNode root;
    
    private AVLNode insert ( AVLNode current,int val)
    {
        if ( current == null)
        {
            return new AVLNode(val, 0, null, null);
        }
        else if ( val < current.val)
        {
            current.left = insert ( current.left, val);
        }
        else if ( val > current.val)
        {
            current.right = insert ( current.right, val);
        }
        else
        {
            return current;
        }
        return current;     // I don't want to return you ////      
    }


public void  add ( int val)
    {
        this.root = insert ( this.root, val);
    }