Unable to save data when clicking on Add button

Hi,

I have repeating field with an default value, so I used add Instance but when I click on "+" button another instance is getting added but the value is also getting repeating. My requirement is whenever an new instance added it should be empty so that user can entry it easily. I have tried the below script.

But the problem is when ever I click add all fields that are added dynamically is getting reset. Can anyone help me please.

Page1.Chapter1.Subform.STP.instanceManager.addInstance(1);

var addCount = Page1.Chapter1.Subform._STP.count; //.instanceManager.instanceIndex;

    for(i=0;i<addCount ;i++)

    {

        if(addCount >=2)

        {

        xfa.resolveNode("handleManualLettersReq.Page1.Chapter1.Subform.STP["+(i+1)+"].Cell3").raw Value = "";

        }

    }