Hello Muhammad,

I have been investigating into the behavior you are seeing, and I am curious to know what your data source looks like in this case? I ask, as I have put together a sample with 100 points, and the null data points do not draw markers, as shown below:

This data source looks like the following, where “Number” is the value member path of the line series:

public initData(){
      let _data: any[] = [];

      for(let i=0; i<100; i++){

        let item = { Label: "Item " + i.toString(), Number: i};

        if(i < 40 && i > 20){
          item.Number = null;
        }
        _data.push(item);
      }     
      this.data = _data;
}

Please let me know if you have any other questions or concerns on this matter.