javascript code help needed

Hi,

My remove function is not working properly, can anyone give my a hand here of what im doing wrong. It is a linked list in javascript. It is adding but not removing the Beginning of the list.

Code:

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function List() {
 this.head = {data:null, next:null};
};

List.prototype.add = function(data) {
        var node = {
                data: data,
                next: this.head
        };
        this.head = node;
};

List.prototype.remove = function() {

        this.head.data = this.head.next.data;
         
          return this.head.data;

};

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Code:

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var mL = new List();
        mL.add("First Element");
        mL.add("Second Element");

mL.remove()

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